What am I doing wrong? (A long read but I need help bad.)

Oreo

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May 6, 2010
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I can't get dwarf hair grass to grow. I can't get anything to form a carpet which is really my goal but this time I wanted to give it a full effort with something easy to increase my chance of success. This is the second time I've planted a ton of DHG only to have it all whither away. So I keep thinking I must be overlooking something obvious, or I must be making some major fundamental mistake to have such consistent horrible results. Thus, I hate to even ask the question here 'cause I feel like I've read all the usual answers already but I'm desperate now and I need someone to tell me why I'm failing so miserably.

My aquarium: It's a 110gal tall (48"x18"x30"high) I have a concrete background that takes up a lot of space and I keep the water level a few inches low so the total system water volume is about 80gal.

Lighting:
I'm using a nova fixture (crappy / no reflectors) with two T5HO bulbs (a plant grow bulb & a 10,000k bulb) fixture sits right on top of the aquarium.

Substrate:
Seachem black flourite sand, 2-3" deep

Filtration:
Closed loop canister style. It's a major (high quality) DIY job with about 15gpm of flow or 11-12 turn-overs per hour. I don't do water changes per-se. I have a constant-drip system that flows carbon-filtered tap water into the aquarium at about 40gal / week. The aquarium has an overflow plumbed to a drain.

Water temp:
is kept at 81*F and far as I can tell stays there very consistently. (+- .5*F)

Ferts:
I've been testing the macro-nutrient levels directly with a spectrophotometer and they have never been limiting. If anything they've been on the high side, especially the nitrates. I dose micros (CSM+B) when the iron residual tests low.

CO2: I'm at the max that my fish can take and I have reasonable confidence based on my pH meter that the CO2 level is steady & consistent at that level for the entire 10hr photo period. I say that because I've kept a close eye on the pH reading all day most days and the pH fluctuates between 6.47-6.55. Any lower then 6.50 and my fish reliably show clear signs of stress. CO2 is turned off when the lights go out & back on several hours before the lights come on.

I also dose twice the recommended daily amount of Excel. In the past I've also dosed twice the recommended daily amount of Florin Axis (a non-glutaraldehyde carbon supplement) I've been out of Axis for several weeks though.

Algae: It's on the rocks & glass but not on the DHG. I can tell that I'm very close to the proper CO2 threshold when the algae (bba & green dust) starts going away after a few days or so but if I forget to dose excel for a day or two the algae comes right back. The long-term average is that algae is growing though. It's not going away. Again, it's not on the DHG.

Livestock:
A blue peacock cichlid, a few mollys, a couple silver dollars, a big ghost knife, a guppy, a few gouramis, and a couple severums. I'm aware that the fish do pick at any & all plants I've tried to grow it's not usually severe enough to prevent a healthy plant's growth. In this specific case I'm confident that if the DHG would just grow it would easily out-pace the fish.

Plants:
After a bunch of failed half-assed attempts to get a carpet plant growing I got tired of my non-scaped mish-mesh of plants & ripped everything out. I decided to just focus on a carpet & then come back for the other plants later. I bought a very nice five square inches of DHG (parvula) from another forum member, separated it into 2-3 plantlet bunches and was able to cover most of the substrate in my aquarium with plantlets spaced about every half inch in more or less a grid pattern. After a couple weeks I noticed the original blades of grass dieing off and new ones very slowly taking their place but the net-growth has been negative over the last month and a half. Of the original plantings there are maybe 25% still showing signs of life. Much of the substrate that had been planted with DHG is now completely bare.

Known Challenges: I have a very tall tank (30") and I don't have a PAR meter. So I can't be certain about my light level at the substrate. From what I've been able to find here & on other forums I'm somewhere in the "medium light" range but it will always be a difficult balance to find in a tank this tall.


So what the heck am I missing? Any ideas? If I had the money I'd offer to fly Tom out to Baltimore for a couple days to get a set of first hand experienced eyes on my setup but that's not going to happen.

Thanks for taking the time folks.
 
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Biollante

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Hi Oreo,

Can you tell us about the concrete background?

What kind of wattage, periods are we talking with the light? I confess I am not a fan of “grow bulbs” or 10,000k for that matter. I think you would be better served with 5500-6700K bulbs. :gw

I assume the Excel double dose is to fight the algae. I would back off on the Excel for the moment as in over the course of a week-or-two back-off to less than half label dose, perhaps quit entirely. :)

That is quite an assortment of fish. :D

Biollante
 

scottward

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Oct 26, 2007
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CO2: I'm at the max that my fish can take and I have reasonable confidence based on my pH meter that the CO2 level is steady & consistent at that level for the entire 10hr photo period.

What about dissolved oxygen levels? If your DO levels are poor, I don't think it takes much CO2 in the water to cause fish stress....? Sorry if I missed it in the detail above, but are you providing any (mild) surface movement to keep the DO levels in check?

The lighting and nutrients sounds pretty good to me...I think checking the DO and pushing the CO2 higher might do the trick?

Would the other gurus on here agree with the statement 'bugger the pH readings' ?? :)
 

dutchy

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I think light is your problem. First: The plant grow bulb puts out just half the PAR compared to a normal daylight bulb. Second: Your not using reflectors.

I'm using no reflectors on my tank, with a distance bulbs / substrate of 20 inch I get around 50 micromols at the substrate. I measured with my PAR meter that the light drops around 10 micromols every 4 inches. Since your tank is 30 inch, I estimate that the distance bulbs / substrate is 26 inch. That means the PAR would be around 35 micromols, if you were using normal daylight bulbs. Since you're using a plant grow bulb you have to take out 25% extra, which gives you around 26 micromols at the substrate. That's very low, the plant might be below LCP.

So, what I would do is change the plant grow bulb for a normal daylight bulb and mount reflectors. But do this gradually, not all at once. The total amount of micromols would raise until around 50.

Do a 50% waterchange every other day to get rid of the algae spores. Brush the rocks and bleech.

regards,
dutchy
 
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Oreo

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May 6, 2010
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I'm not using Excel to fight algae really because I'm not dosing high enough for that. I'm using Excel (& occasionally Axis) mainly as a carbon source to supplement the apparently inadequate CO2.

I can (but haven't) tested dissolved oxygen levels. What level is ideal? Surface agitation is quite strong IMHO. I've got all 15gpm flowing from a single outlet over the surface of the rock wall (and down into the aquarium. It's a high-volume low intensity flow, so not like a power-jet or anything but the current does create micro air bubbles that get carried all the way down to the substrate and 3/4 the length of the aquarium before most of them rise back to the surface. It's easy to get an idea of what the water flow is doing in the aquarium just by watching the bubbles. On the other hand there is hardly any plant bio-mass in the aquarium now to convert CO2 to O2. I've been half tempted to try injecting pure oxygen in addition to the CO2 just to see if the fish do better with higher CO2 levels. I already have an oxygen tank & regulator for it.

Keep in mind, I'm not measuring CO2 with the pH meter absolutely. I'm only using the pH meter as a relative reference. Ie. to say however much CO2 was in the water yesterday at 6.50pH, the same amount is there today at 6.50ph. The number consistency has been confirmed on numerous occasions by the fish behavior. Specifically, during feeding time if I'm pushing too much CO2 my cichlids act sorta spacey and half conscious like they can't get a good aim on the black-worms in the water. Normally the cichlids are ravenous eaters and have no trouble with getting the worms. (I've never seen gasping at the surface from them though, even when they totally passed out a couple times & needed to be moved to a hospital tank briefly to be revived.)

One note on the pH is that as more CO2 is added to the water the pH drops but at an increasing rate. So that the difference in the amount of CO2 in the water between 7.50 and 7.00 pH is much less then the difference between 6.55 and 6.50. It's entirely possible that 6.50 is an adequate amount of CO2 and 6.55 isn't enough but to do any more consistent then that I'd have to do some serious re-engineering of my very typical CO2 delivery system.

Here's some OLD pictures of my aquarium. (None of the fish or plants in this picture are in the aquarium now)

p1061531.jpg


p1061520.jpg


p1061526.jpg


Here is the filter outlet (pictured above & below.) In this picture there was 6 gpm. There is now 15 gpm, so more then twice as much flow as in this pic. (I upgraded the pump)

p1061528.jpg


Pictured below is the OLD filtration system. The new one has almost three times the capacity for flow, media, etc. I'm still using the same Hydor ETH 300w heater but I upgraded the canisters, the pump, I added a third flow meter (they're run in parallel), improved tap-water drip metering system, and the UV unit (which I'm not currently using because it removes the iron residual) and of course the pressurized CO2 system was added after this pic was taken also.

p1091537.jpg
 

Oreo

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dutchy;56014 said:
I think light is your problem. First: The plant grow bulb puts out just half the PAR compared to a normal daylight bulb. Second: Your not using reflectors.

I'm using no reflectors on my tank, with a distance bulbs / substrate of 20 inch I get around 50 micromols at the substrate. I measured with my PAR meter that the light drops around 10 micromols every 4 inches. Since your tank is 30 inch, I estimate that the distance bulbs / substrate is 26 inch. That means the PAR would be around 35 micromols, if you were using normal daylight bulbs. Since you're using a plant grow bulb you have to take out 25% extra, which gives you around 26 micromols at the substrate. That's very low, the plant might be below LCP.

So, what I would do is change the plant grow bulb for a normal daylight bulb and mount reflectors. But do this gradually, not all at once. The total amount of micromols would raise until around 50.

Do a 50% waterchange every other day to get rid of the algae spores. Brush the rocks and bleech.

regards,
dutchy
You think I don't have enough light? Seriously? I mean, I've contemplated that idea but when I turn on a third bulb I get somewhat of an algae explosion on the glass (green dust) and on the rock wall (bba everywhere.) Considering I'm already at the max amount of CO2 that I can possibly get into the tank without killing things it sounds like I'm stuck between a rock & a hard place. I thought Tom always advocated a low-light tank anyway? Perhaps I'm in dire need of borrowing or buying a PAR meter to nail that parameter down for sure? I currently run one 10,000k bulb and one plant grow bulb. Would I do better to run just two 10,000k bulbs? (since I already have another 10,000k bulb I could swap in place of the plant grow bulb.)

Removing algae spores in my system seems almost impossible. I'd have to completely drain the tank for that and pump bleach-water through the entire system. Not to mention trying not to lose fish in the process. Is that really a critically necessary move?

Oh, and I forgot to answer Biollante: My fixture holds four T5HO (54w each) bulbs. I've been running only one pair 10hrs / day. I've played with 8 & 9hr /day periods with no noticeable difference really.
 
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dutchy

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Tom advocates low light, not because of low light, but because CO2 demands can be met easier. Can it be done with higher light? Sure. Can it be done with super high light? Difficult. On the other hand, you need enough light to make your plants grow. If you are lower than their LCP, they will die.

If you use reflectors you can aim them in a way that not much light hits the windows, this will give you less GDA. You can also let the flow hit the front window, this will also reduce it. I don't have BBA and I'm using higher light than you. So that doesn't mean higher light causes your BBA, but another nutrient that bottoms out because of more plant growth for which you didn't compensate. If you added a third bulb, that's an increase of 50%. A lot. If I would make an increase by 50% I'd do it slowly, starting with 2 hours per day and slowly more.

I get BBA too, when I make a mistake. The most frequent one is inconsistent CO2. Fluctuating levels. But when I get it, it takes me only two, three weeks max to get rid of it. Pick and prune is an important one here. Concerning the rocks, I didn't see the pics until now. What you could do is drain the tank like 75% and spray a 50% dilluted Excel solution on them, wait 5 minutes, the scrub and refill. Be careful it doesn't hit your plants, you will destroy them. Still I'd do 50% waterchanges every other day.

You could use something like a 6500K for the other bulb. With two 10000K the colours get kid of washed out. Or you could start first to mount reflectors. Maybe it's enough.
 

Oreo

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May 6, 2010
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Mounting reflectors would be a difficult option because my fixture has no room for them. I mean, if it has to be done then that's what I'll do. I'll figure a way or buy a new fixture if I must. It would be easier if I could somehow get the right amount of light from the fixture I have. Even if it means using using too many bulbs but cutting back the light with window screen or some other way of moderating it. That method won't keep the light off the front glass the way you describe though. I guess I'm a little bitter about having bought an expensive (for me) fixture only to have it not work as well as I thought.

As for using Excel on the rocks to kill the algae... I've got a lot of surface area to cover. 20ml diluted to 50% = 40ml = a full shot glass. I guess I could do it that way but it's gonna take a week or so like that without over-dosing.
 

Biollante

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Hi Oreo,

As I am writing to Guru Team members, I know my expertise is not near anyone here. :eek:

In my experience light will not be the principle problem, if you wish to bump it up a bit form an aluminum foil reflector for now. White card stock will boost the light 10% or so.

I stand by the getting rid of the Excel, for now anyway.

Fluctuating CO2 is worse than low CO2.

A massive water change would be a good idea, failing that a Potassium permanganate treatment would help.

In Baltimore at 81F (27 C) dissolved oxygen of around 8mg/l would be excellent.

I actually do not think your problems are overwhelming, just feels that way. :cool:

Biollante
 

dutchy

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I just made a test setup with two 24 Watt T5's and measured them at 25 inch in open air. One was a 6500K, the other one an AquaMedic Plant Grow. Without reflectors I got a combined PAR of 16 micromols. The Plant Grow gave only 2 micromols at this depth. :(

Then I measured my own tank, I switched off two rows of T5 and measured just the remaining two rows of T5 without reflectors. Both bulbs are daylight types. I measured at a depth of just 20 inch. Result: 30 micromols.

That should give you some usable data.

regards,
dutchy
 

Oreo

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May 6, 2010
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Dutchy,

So what you're saying is that your couple of tests there are a reasonable approximation of the amount of light I'm using and that amount was found to be woefully inadequate. That sound about right?

As frustrating as this light issue is that is very helpful and I thank everyone for their responses so far. Here I was worried that I was bordering on too much light and come to find out I need almost double. That very well could be my problem.

For now, I've turned on a third bulb and cut my photo-period from 10hrs down to 8hrs. When I get time (lord knows when that will be) I'll pick up some reflectors and go about re-engineering my light fixture. That will probably help a great deal I think. I do hear what you guys are saying about increasing light slowly but I've got nothing to lose right now. I'm essentially starting with a bare tank. I'm just gonna make the adjustments all the way & be done with it. There's nothing in there that needs to be acclimated other then a few wisps of DHG. I'm going to have to buy more of that for a fresh start once I get my problems sorted anyway.



Biollante,

I am (not perfect but) very consistent with my excel dosing. You think this could be causing a problematic fluctuation in CO2 levels? I miss a dose maybe once every other week.

Why a massive water change? What's Potassium permanganate? An algaecide?

8mg/l dissolved oxygen- good to know thank you. I'll make a point of testing this in the near future to see where I'm at.

My problems aren't overwhelming per se, but they're beyond my ability to figure out on my own right now and I'm way too invested in this hobby (in terms of money, time, and enjoyment) to be failing so miserably. I am supremely frustrated at this point so I appreciate you guys taking the time for me.
 
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Tug

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8mg/L of Oxygen could be considered to be 100% saturated. Anything above 6mg/L should still be fine to drive metabolic processes. That's not to say you wouldn't be better off with 8mg/L.

Hang in there.
 

Gerryd

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Hi Oreo,

A few random thoughts......

I would NOT assume the c02 concentrations are EQUAL day to day based on a ph reading and/or lsck of fish stress. C02 changes a lot in space and time and many factors can affect it.

Here is what I would try, doing my best to distill all the great advice you have already gotten, and a few thoughts of my own:

1). Let's see if the lighting you have can grow plants PERIOD, forget about a carpet plant for right now.

a). Get some nice rotalas, hygros, ludwigia, etc and see if THEY will grow with your current regimen. Also toss in a bunch of reg java fern for fun. If that won't grow, you have REAL issues LOL

Since the stems will be taller they will be closer to the light source as it is now.

b) get a few bunches of each and plant as follows:

I. Trim the stems so you only have nice tops which are the growing tips. Remove any of the stem that is rotten.
II. Remove the leaves from the bottom 1-2" of each stem. So, ensure you leave enough from #1.
III. Plant each stem about .5" apart and plant groups. You want room for them to grow and get current thru there.

2). If you are now close to c02 stress for your fish, I suggest you get a small powerhead or route an outlet to ensure that the surface is NOT like a reflecting pool. As long as you have a ripple but do not BREAK the surface, you will be fine. Adding c02 to the water gives a little more leeway with c02.

3. Do you use a drop checker at all? If not, I suggest you get a couple and try them out.

4. Check that your circulation goes ALL over and will make the leaves sway gently.

5. Remove any algae infested plants and toss them.

6. Stop double dosing excel. Only dose as on the label. Many plants do NOT appreciate an excel OD.

7. You can always REMOVE the rocks/wood, spray them with excel, rinse well and replace in tank. More work but worth it in some cases.

8. Stick with 7-8 hrs photoperiod for now.

9. Large water changes will help a lot. I know you have a drip system, but changing 50% of the water every 1-3 days while having issues is beneficial in many areas. They add micros, remove much waste, add 02 and c02 to the water, help remove algae spores, etc.

You will NEVER eliminate algae spores in an aquarium. You can however control the OUTBREAKS of such spores with healthy plant growth. While the reasons for this are not quite clear, it does seem to be the case over and over.

Misc:

I think you have a lot of fish which will get bigger than they are now. I would suggest dumping the concrete background as it simply uses too much viable space and water volume :) My opinion only. I like the way it looks, but just too big for me.

You may find your mollies eaten pretty soon as well...

Hope some of this helps.
 
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Whiskey

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Aren't silver dollars huge plant eaters? I had some in an oscar tank, and I used to feed them my green leafy trimmings, and they would tear through them in no time.

Whiskey
 

Oreo

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May 6, 2010
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Thanks for the reply Gerry. My responses in blue:

Gerryd;56048 said:
Hi Oreo,

A few random thoughts......

I would NOT assume the c02 concentrations are EQUAL day to day based on a ph reading and/or lsck of fish stress. C02 changes a lot in space and time and many factors can affect it.

Here is what I would try, doing my best to distill all the great advice you have already gotten, and a few thoughts of my own:

1). Let's see if the lighting you have can grow plants PERIOD, forget about a carpet plant for right now.

a). Get some nice rotalas, hygros, ludwigia, etc and see if THEY will grow with your current regimen. Also toss in a bunch of reg java fern for fun. If that won't grow, you have REAL issues LOL

Since the stems will be taller they will be closer to the light source as it is now.

b) get a few bunches of each and plant as follows:

I. Trim the stems so you only have nice tops which are the growing tips. Remove any of the stem that is rotten.
II. Remove the leaves from the bottom 1-2" of each stem. So, ensure you leave enough from #1.
III. Plant each stem about .5" apart and plant groups. You want room for them to grow and get current thru there.
I can grow some stuff under the current conditions. Not everything grows well and some plants get eaten more then others. For instance, stem plants that the fish don't like tend to grow fine. Swords of all types grow pretty well. I had a tiger lotus that would grow quite fast sending new leaves up towards the surface on long stems but the fish always chomped the stems. Anubias grow slowly and tend to accumulate bba on the leaves in the long run. Java fern and borneo fern never did grow well for me.


2). If you are now close to c02 stress for your fish, I suggest you get a small powerhead or route an outlet to ensure that the surface is NOT like a reflecting pool. As long as you have a ripple but do not BREAK the surface, you will be fine. Adding c02 to the water gives a little more leeway with c02.
I covered this in a post above. I've got a lot of surface agitation.

3. Do you use a drop checker at all? If not, I suggest you get a couple and try them out.
Not yet. I may consider it at some point but I whole-heartedly subscribe to Tom's feelings on the matter. A drop checker leaves a huge margin of error and as such has a very limited usefulness. I really need to get back on that NDIR meter. It would be the definitive answer on CO2. In the mean time I have a titration test that I can use to spot check CO2 levels. Not ideal but it could add or reduce support for my confidence in the pH meter's readings as they relate to CO2 content.

4. Check that your circulation goes ALL over and will make the leaves sway gently.
In so far as the DHG is concerned, some of it gets blasted by the filter output, some of it gets only enough flow to barely move the tips and some of it gets everything in between. The full range of flow is represented well in my tank and DHG isn't growing well anywhere. The few wisps that are still showing signs of life are growing in the area with a slower current but it could also be due to the fish showing less interest in that area.

5. Remove any algae infested plants and toss them.
This is currently a non-issue.

6. Stop double dosing excel. Only dose as on the label. Many plants do NOT appreciate an excel OD.
As mentioned above, I may have to give this some thought. None of my plants except the vals ever seemed to mind the Excel, although I can't say I've noticed any great benefit to it either.

7. You can always REMOVE the rocks/wood, spray them with excel, rinse well and replace in tank. More work but worth it in some cases.
My concrete background is permanently attached in my aquarium. It can not be removed and there are no other hard-scape items.

8. Stick with 7-8 hrs photoperiod for now.
Done. As of yesterday I switched from a 10hr period to an 8hr period.

9. Large water changes will help a lot. I know you have a drip system, but changing 50% of the water every 1-3 days while having issues is beneficial in many areas. They add micros, remove much waste, add 02 and c02 to the water, help remove algae spores, etc.
I've been thinking about the possibility that for what ever reason a regular water change routine might be superior to a drip system. This seems like a long-shot to me but I admit since I'm clearly failing with the drip system this might be worth trying for a while.


You will NEVER eliminate algae spores in an aquarium. You can however control the OUTBREAKS of such spores with healthy plant growth. While the reasons for this are not quite clear, it does seem to be the case over and over.

Misc:

I think you have a lot of fish which will get bigger than they are now. I would suggest dumping the concrete background as it simply uses too much viable space and water volume :) My opinion only. I like the way it looks, but just too big for me.
Dumping the background is simply not an option right now. It's not a bad design at all, but it does leave plenty of room for improved functionality in a planted tank. In the future I'd like to get a larger aquarium and use the lessons I've learned to improve the background design. But that's probably a year or so down the road.

You may find your mollies eaten pretty soon as well...
My fish have gotten along quite well actually for over a year now. The mollies are quick agile fish that are in no danger at all. I can't ever remember one being eaten. The peacock cichlid is fairly docile and the severums mostly chase each other around. The 10" ghost knife keeps to herself most of the time under one of the rock-ledges. The silver dollars do eat the plants but not enough to prevent a net-positive amount of growth, especially when the aquarium has lots of plants in it to share & distribute the abuse done by the fish. The only time I have to worry about fish getting eaten is during the first week or so after their introduction. After that the more aggressive predatory fish tend to leave them alone. Even the slow little fan-tail guppy.


Hope some of this helps.
 
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Oreo

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May 6, 2010
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UPDATE:

Got my hands on an Apogee PAR meter. (Actually, I just broke down & bought one.)

I tested the amount of light that I had been using while having problems and got about 30 micromols. You guys still think that's not enough light to grow plants?

After I cleaned the plexi-glass cover on my light fixture I gained 5 micromols. Then I tested the 10kk and plant grow bulbs individually. They only differ by about 2 micromols. Each single bulb in my setup gives about 20 micromols at the substrate so just by removing bulbs from the fixture my four choices are: 20, 40, 57, and 75 micromols. You guys have any preference for one of those numbers?
 

jcardona1

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Jul 12, 2008
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Hey Oreo,

Thought you'd find this interesting. I did some PAR testing with a few fixtures of my own. I posted this over on plantedtank, but here's the info. I would try to increase it to at least 50 micromols at the substrate. That seems to be a good figure from what I've read. Hope my results help a bit, because I believe you have the same fixture I tested

jcardona1;1178079 said:
Hey folks,

Just wanted to share the details of some recent PAR testing I did. I borrowed a PAR meter from my local club (Hoppy and Tom). I wanted to compare this to the light fixtures I had to see how reliable the information is, because we all know every fixture and light bulb is different. I think you'll see that PAR charts are meant to only be used as a rough guide. The only real way of knowing how much light you have is to test YOUR specific setup. There are way too many real world variables that will affect readings from one tank to the other.

Here's some important things you should know about my testing:
1. The Lowes and Current/Nova fixtures were tested on a standard 20g tank, with water. The sensor was placed in the middle of the tank, right under the fixture.

2. The Lowes & Current/Nova lights are 48" long, and the tank is only 24" long. To avoid having any stray light afftect the reading, I wrapped the overlapping section of the fixture with a towel. Removing the towels caused an increase of 4-5 micromols.

3. The Lowes fixture is black metal, even where the bulbs are. This is obviously isn't a good color for reflection, so I also wrapped the inside with aluminum foil and took more readings.

4. The Current/Nova fixture uses two bulbs, very close together. This has a very cheap thin aluminum reflector that goes over both bulbs.

5. The bulbs in the Lowes & Current/Nova fixture are fairly old, all over a year. Please keep this in mind as new bulbs may give a higher reading. The only bulbs that were brand new were the Giesemann bulbs in my Catalina fixture (3 days old at the time of testing).

6. I only took one reading with the Catalina fixture since it's mounted to a hanging bracket and the tank is heavily planted. I may try some more readings, but for the time being, it's just at 28". Also note that this is a 4-bulb fixture. I only tested 2 bulbs, in the outer most banks.

7. For the Current/Nova fixture, I had 3 types of bulbs. I took individual readings from each bulb and compared the results as seen below. Again, keep in mind that bulb age may be a factor. I did not go out and buy new bulbs to test this fixture.

Any questions please feel free to ask! I have a few more desktop lamps/fixtures that I will be testing in the days to come
smile.gif



 
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Oreo

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May 6, 2010
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16
So what is better: 57 or 75 micromols? Would 75 be too much / high-light?
 

jcardona1

Junior Poster
Jul 12, 2008
11
0
1
Me personally, I'd keep it at 57. Tom has said that most of his tanks are 40-50 at the substrate, as well as some ADA tanks he's tested.

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