How to keep consistent CO2 rates with a pressurised system? Loosing my mind!!!

[tchavei]

Hi all

I've a inline CO2 Atomizer that is mounted right after my external filter (Eheim Eco Pro 130). I'm using a 2Kg CO2 Bottle with a dual stage regulator, needle valve and solenoid valve. The CO2 comes up 2 hours before the lights and turns off 1 hour before the lights go out (6 hour period). The pressure that goes to the atomizer is set at 1.9 Bar since my solenoid valve recommended pressure is 2 bar maximum.

During the last week, I noticed that Staghorn Algae started to creep into my aquarium. I did some research and found that it should be mostly because of inconsistent CO2, dirty filter and probably poor flow. Although my 16 gal aquarium has a 10 times turnover provided by my filter, I added two wavemakers just to be sure that my CO2 would reach every corner of the tank, cleaned my filter and upped the CO2. After cleaning the hoses and the external atomizer, I noticed that the CO2 instantly went up in bubble rate (from maybe 6 to 10 bps). There was pearling everywhere. My dropchecker went into bright yellow and as I noticed my fish starting to gasp for air, I adjusted the flow to maximize the CO2 while keeping the fish calm (not quite happy but calm). I ended with maybe 8 bps which seemed to be right in the ball park for the last 3 days (pearling everywhere... even the staghorn got full of trapped CO2 bubbles). Anyway... today I noticed that the bubble rate dropped again. I checked the Atomizer (and gave it a quick clean with a brush) and the CO2 skyrocket again.

Now keeping in mind that an inline Atomizer isn't very easy to clean (you need to shutdown the filter, remove the hose, blow the water out, clean the inside of the atomizer with a brush and assemble everything again), I can't do this every night to keep the atomizer's ceramic tube pristine in order to keep the CO2 rate consistent and get rid of the staghorn (not to mention that my plants surely appreciate consistent CO2 even more).

What should I do? Are normal ceramic glass diffusers more consistent? I kinda like how the atomizer spreads the co2 microbubbles everywhere. I can't achieve the same using a glass diffuser inside the tank. I think that the major problem with the atomizer is that, since its permanently in contact with the flowing water (600L/h) its slowly starts clogging up.

Is there any other method? I've seen the aquamedic reactor 1000 (quite pricey). Do you think that this would do the trick in providing more consistent CO2? Would it clog up as fast as my atomizer?

Btw, I'm using the EI method for fertilization. Right now it appears that nutrients are not the limiting factor (neither is the light... 10 x Cree XP-G Leds DIY... 4000 Lumens) so that only leaves CO2.

Thank you very much

Here is a pic of my atomizer, CO2 setup (before I installed the solenoid valve) and my tank (before staghorn kicked in):

Regards

Tony

 

[Biollante]

Nosey Creatures Them Evil Plant Monsters Is

Hi Tony,

A quick question or four.

How long has the tank been operating?

How long since cycling?

Did the staghorn start after the change in your system?

What kind of crud is plugging your diffuser?

I am not a fan of visible bubbles so I’ll let someone from the Military-Industrial-CO[SUB]2[/SUB] Complex answer your general CO[SUB]2[/SUB], questions.

Biollante

 

[Biollante]

Not So Bad, Losing My Mind, Really Wasn't Using It Much...

Hi Tony,

Meant to add, of course you are losing your mind, probably lost it some time ago.

Planted tanks are major symptoms; in fact more than enough for a diagnosis, add to that you are on this forum, conversing with an evil plant monster.

There’s a guy running around, I am not making this up, no matter what you ask he’ll tell you the answer is CO[SUB]2[/SUB], no fooling, :excitement:worst part is he is right most of the time.

Losing your mind really isn’t all that bad, much of life makes more sense this way.:tan::02.47-tranquillity:

Biollante

 

[dutchy]

An AM1000 reactor won't clog, thus providing more consistent CO2 without the cleaning. You also might notice a reduction in CO2 consumption, because of better CO2 mixing. In a big reactor the water flow is slowed down so there is more time to dissolve the CO2.

Staghorn is often also caused by short NH4 spikes after working in the substrate. Always do a big waterchange after that.

You might want to use Excel for some time, this kills staghorn.

 

[tchavei]

Hi all

Thank you for all the input so far. Answering the questions that came up:

How long has the tank been operating?
The original tank had over a year. I transferred my live stock and my filter for a couple of weeks to do a major reshape. I basically set it up from scratch. That was on March, 19th.

How long since cycling?
Although I used the cycled filter, the added biomass (only had a couple of anubias before) and the conversion process from emersed to submersed which resulted in a lot of dying leafs, created an ammonia spike. The filter took around three days to take over the ammonia and over two weeks to control the nitrites. The tank finally was clear of ammonia and nitrites by Abril 10th. I haven't seen ammonia or nitrites since. So I would say about a month after cycling.

Did the staghorn start after the change in your system?

The staghorn started a week after I started to dose micros on Abril, 14th. I didn't start Macros at the same time because I didn't had the chemicals yet so I used a comercial fertilizer (Elos Planta 1 & 2) because I knew it had potassium. I finally got a hold of Macros last week and replaced the comercial fertilizer with my mixture on Abril 26th. I noticed the first signs of staghorn on the 27th. The staghorn has been slowly growing even with tons of CO2. I read that it probably wouldn't go away once estabilished unless I dose Excel but I would have expected that it would at least stop growing.

The only change I can remember that might have caused this outburst is that I turned the Wavemaker off a couple of weeks ago because my neons don't seem to like the current. They keep hiding away from the lights and the current. After I noticed the outbreak, I turned the Wavemaker on and added another one. Even in a lot of current, the algae keeps growing.


What kind of crud is plugging your diffuser?

I would say its the same biofilm that slowly covers the inside of the hoses. I usually clean my hoses once a month but since I noted so much difference in CO2 diffusion, I tried to clean just where the atomizer connects after just 3 days and there was a noticeable difference so I assume that the ceramic tube inside the atomizer is more sensitive to this biofilm. The hoses still appear clean (obviously... it has been only 4 days since last cleanup) but the atomizer must be more sensitive.

An AM1000 reactor won't clog, thus providing more consistent CO2 without the cleaning. You also might notice a reduction in CO2 consumption, because of better CO2 mixing. In a big reactor the water flow is slowed down so there is more time to dissolve the CO2.

Thats good to hear. It appears that my filter's flow (500l/h -> 132 gal/h) isn't enough for the AM1000... did you or anybody try out the Sera CO2 Flore 500? Its seems quite nice and also just as open as the AM1000 so probably won't clog also?

Staghorn is often also caused by short NH4 spikes after working in the substrate. Always do a big waterchange after that.

You might want to use Excel for some time, this kills staghorn.

I don't remember messing with the substrate. Maybe cutting off a lot of tenellus runners as the weed wants to cover my HC cuba but nothing major like replanting or pulling plants.

Here is a pic of my tank on the day I did the re-scape. Plants have been growing fine. The tenellus is almost incontrolable. The Cuba is kinda slow and the lilaeopsis is even slower but thats normal I think since they both arn't fast growing plants.

Regards

Tony

 

[maknwar]

Those needle valves are also known to be hard to dial in. Not sure if thats your main problem, but im sure it doesnt help.

 

[tchavei]

They are?

So... you mean that the adjustments I sometimes need to make from one day to the next might be because of the needle valve and not the atomizer getting clogged? I do notice that when I don't touch the needle that in about 3-4 hours the bubble rate gets higher but I attributed that phenomenon to the fact that the atomizer might get unclogged a little bit as the photoperiod passes and the CO2 is constantly flowing through the atomizer's walls?

Is there something that would be easier to dial in than a needle valve?

Thanks

Regards

Tony

PS - The staghorn is getting worse and worse despite all the tons of CO2 I've been adding... at this rate, I'lll empty my 4lb bottle in a month. I ordered some Excel. Should be here by monday so I give the algae a kick in the butt but I wish I could find the root cause. Even if something happened a few days/weeks ago, Ain't I'm doing everything right now? Shouldn't it at least stop growing/spreading? I'm not asking for it to drop dead (well that would be nice but I doubt it) but at least the growth should be affected and its not.

 

[Left C]

I agree with maknwar. Your needle valve may very likely be the culprit causing the inconsistent CO[SUB]2.[/SUB] level. Some needle valves just will not hold their rate because of slop in the machining process when the valve is made. Some needle valves are temperature sensitive. This is from incompatible materials used. There are other reasons too. but you get the idea, I'm sure.

Swagelok low flow metering valves are very good. They are available world-wide. I really like Ideal's "1" series needle valves in either brass or stainless steel. These valves are very good for our use.

 

[tchavei]

Thank you for the links. I will see if I can get my hands on one (preferably second hand as they are quite expensive). I spent a few hours around them already but didn't knew exactly which ones were suited for our application. Thank you for that

I'm currently injecting 8 bubbles per second. Dropchecker is always in the yellow zone. My fishes seem not to mind so I'll just keep an eye on them. I really don't understand how people are talking about 1 or even 0.5 bps in tanks twice as large as mine. I can't see how they can have a high CO2 content. Obviously bubble size is very different from bubble counter to bubble counter but even so... 8 bps is very high and I have a smooth water surface ripple so Co2 isn't wasted that much. I kept raising the CO2 until the HC started to pearl and that's when I checked and came up with 8 bps... oh well. As long as fish and plants are happy, who cares anyway (besides my wallet when my bottle empties).

Btw, I just found out that my bristlenose plecos mated and I saw some of the fry today... will excel harm them?

Thank you for all the kind input once again.

Best Regards

Tony

 

[Left C]

Congradulations on the fry. I really don't know how sensitive they are to Excel, but to be safe you may want to back off completely or use it at a lower dose. If you were using Excel when the plecoes laid their eggs, I don't know if eggs are less sensitive than fry.

I'm just rambling and guessing right know. I really don't know what to say about Excel use and fry.

If you can find a low flow Swagelok metering valve with 1/8" threaded connections, that will be the ticket. Another good choice would be one with 6mm or 1/4" tubing fittings. One with other sizes tubing fittings can be fitted with many various Swagelok adapters and fittings to make it work.

Parker is another good company for metering valves.

Do not use Swagelok, Nupro, Whitey, Parker, etc needle valves. They are much too coarse for our use. Go with the finer control of their metering valves.

I prefer the following Ideal needle valves:
52-1-12: brass, angle flow, 1/8" NPT male threads, knob handle
V52-1-12: brass, angle flow, 1/8" NPT male threads, Vernier caliper handle
52-1-11: brass, straight flow, 1/8" NPT male threads, knob handle
V52-1-11: brass, straight flow, 1/8" NPT male threads, Vernier caliper handle
54-1-12: stainless steel, angle flow, 1/8" NPT male threads, knob handle
V54-1-12: stainless steel, angle flow, 1/8" NPT male threads, Vernier caliper handle
54-1-11: stainless steel, straight flow, 1/8" NPT male threads, knob handle
V54-1-11: stainless steel, straight flow, 1/8" NPT male threads, Vernier caliper handle
Maybe you can find some used Ideal needle vfalves, but they are rare. Bill Sand is the one to contact at Ideal.

 

[tchavei]

Jeez!

Now that's an long list you came up with

Unfortunately, living oversees, its kinda hard for me to get an Ideal valve. I'm sure they are great but kinda unreachable for me. I did send Bill Sand an email for a 52-1-11 but not sure he will answer. I did spent the whole day looking for meter valves and its easier for me to find Swagelok ones than any other brand. Guess its because they make them in Switzerland which is closer to me than the US. I did find several interesting ones like the "SS-SS2" although this particular one made me scratch my head because if I read the Datasheet correctly, the maximum flow is just 0.004 Cv... I'm not an engineer so I have no clue if that's enough for our application but I wouldn't want to have it fully open and only get like 1bps. I guess I will have to study this stuff a lot more. Anyway, I'm definitely convinced now that my problem is indeed the needle because I don't believe the inline diffuse changes pressure so much from day to day basis. I also noted that my needle vale sometime only needs a very light touch do go from 3 to 6 bps. Doesn't make sense that the diffuser back pressure would change so much with just a hairy touch on the needle valve.

About the fry, its not the first time my bristlenose mated (although the first time in this new layout) but the last time, the 7 youngsters I had, suddenly died in a matter of a couple of days at a month age. Not sure what the cause was although I suspect that my suddenly rigorous weekly WC to keep the water clean were the culprit. The eggs hatched at a time when I was kinda relaxed with the aquarium so there were a lot of nitrates present. When I discovered the fry and started to watch the parameters like a hawk, I basically killed them... live and learn...

Thank you VERY VERY much for all the input you've gave me so far. I will try to get a nice valve to keep my CO2 stable. I already hijacked another thread on the classified section about a metering valve. Maybe I will get lucky.

Best Regards

Tony

 

[maknwar]

sent you a pm Tony.

 

[tchavei]

Got it and replied

Regards

Tony

 

[Matt F.]

I've only run into staghorn when I've kicked up the substrate due to replanting, trimming, or mowing the lawn. I am always on top of lightly vac-ing leaves and the substrate after such a venture. I use CSM+B micros and powdered macros, so nutrients aren't an issue. I'd say crank you co2 up a bit more...HC is a good plant to watch when it comes to co2 levels. Much better than a drop checker. The plant will be slow to spread if co2 isn't high enough. If co2 is good, then you'll be hacking back every couple weeks.

Staghorn is often also caused by short NH4 spikes after working in the substrate. Always do a big waterchange after that.

You might want to use Excel for some time, this kills staghorn.

 

[tchavei]

I understand that now and I've increased CO2 to the point that the reactor isn't coping with anymore bps (I changed to the sera flore 500 a couple of days ago). Some microbubbles are passing to the aquarium as the injected CO2 is surpassing the reactors limit. The dropchecker is a solid yellow, fishes do gasp a little but don't try to reach the surface. Takes around 4 light hours to get the HC pearling. My light period is reduced to 6 hours... I hope this will be enough because I can't do much more.

I'm also dosing heavily with excel and the staghorn started to turn purple... I think I will kill it in the next days/weeks but I would like to prevent it from it happening ever again.

Best Regards

Tony

 

[gsjmia]

I have an Up Aqua 16/22 in line atomizer installed right after my Rio 2500 pump in the wet/dry and had a somewhat similar problem.

The Co2 would almost be non-existent for about an hour or two after first turned on, so I opened the Ideal needle valve-then the fish would be gassed by the end of the day. I thought maybe the regulator was "creeping" so I got a new-used Victor and it didn't help.

I was told that the flow was too heavy and that I should make a "T" at the pump outlet and send two lines to the tank instead of a single line: one line for the atomizer with a ball valve to regulate/slow the flow and the other line to handle the balance of the flow.

I thought about what was going on and thought it was the head pressure that was the problem rather than the rate of flow.

The Rio has a rating (from memory here, may be off) of 700 gph with zero head, and 300gph with a head/lift of 5 feet. So that 400 gph has to go somewhere and it is pressure in the line and the pressure is greatest at the bottom (I have not measured this to know if it is true-just surmising that it is greater at the bottom-that gravity thing and all that).

With the atomizer at the bottom, it has to fight the extra head pressure, the pressure in the line has to build up and then force the water out of the atomizer and then fight its way out of the stone.

If the pressure in the line at pump is say 20 psi, then the Co2 has to exceed 20 psi before it a can be expelled through the atomizer. If the Co2 pressure is 21psi, it will take a long time to build up in the line (if you use silicone hose you can feel the hose swell) and get out of the atomizer (at the rate of 1psi in that example). Over ten years ago I put together a carbonated beverage system in my house and it wouldn't work right because my water pressure was to high (65psi) and the Co2 pressure at the carbonator was about 60psi--no Co2 could enter the carbonator. I put a water regulator on the line to bring the water pressure down to 20psi and then got good soda. FYI, the "carbonator" in a beverage system is a tank that is roughly half water and half Co2 and an electric pump forces replacement water into the Co2 under pressure causing the carbonation.

Maybe same thing here.

Short answer, I moved the atomizer up 4.5 feet from the bottom to the top of the line next to the bulkhead, the head pressure is a lot lower and it works fine-I get a near invisible mist within seconds from when the Co2 is turned on (with a corresponding drop in ph) and it seems stable throughout the day.

 

[tchavei]

Thats pretty interesting. Thank you for the input. I believe I was experiencing something similar because the rate I ajusted at the beginning of the lighting peiod was definately not the Same by the end. Having ano oversensitive needle valve wasn't helping either.

Anyway, I changed to the sera flore 500 a few days ago and I'm liking the system so far. Bps are consistent through the day although there is some intermittent back pressure as the rotor passes near the co2 input hole which make the bubble counter jump a little. Hard to estimate bps now because there are multiple (2 or 3 bubbles) coming up at the same time. I only wish I could inject a little more (currently about 6bps) to get that dropchecker into a shiny yellow but I think I can increase bps anymore without releasing undissolved co2.

I did make a deal with maknwar for a swagelok metering valve so when I get that one, I hope I'll be able to dial in the flow much easier.

Thanks again

Best
Regards

Tony

 

[gsjmia]

With that reactor you won't have to use such high pressure and shouldn't have a inline pressure equalization problem.

 

[Left C]

... I did spent the whole day looking for meter (spelling correction: metering valves) valves and its easier for me to find Swagelok ones than any other brand. Guess its because they make them in Switzerland which is closer to me than the US. I did find several interesting ones like the "SS-SS2" although this particular one made me scratch my head because if I read the Datasheet correctly, the maximum flow is just 0.004 Cv... I'm not an engineer so I have no clue if that's enough for our application but I wouldn't want to have it fully open and only get like 1bps. I guess I will have to study this stuff a lot more. ...

The 0.004 Cv of the low flow "S" series valve is fine for most normal sized home aquariums. Larger aquariums would require a higher Cv. There are some Swagelok medium flow metering valves with a 0.04 Cv that will work too. Many people can find a "sweet spot" when opening them that will give them a good and consistent bubble rate. Some of the medium flow valves will provide too much flow even when first cracked open. This really doesn't make sense since they all have a rating of 0.04 Cv. On another point, take a look at the valves' Cv vs turns open graphs on page 4 on this pdf. Notice that the "S" series valves max out at 0.0040 Cv. Now look at the "M" series valves' graph. Look at the shape of the graph when the valve is first cracked open. Notice that graph is almost horizontal for the first 1/2 to 3/4 of a turn. This has a Cv from approximately 0.001 to 0.002 which makes up nearly half of the "S" series valves' Cv shown in the graph. After that, the graph is at a 45° angle and too much flow. Somewhere in that horizontal area or a little ways more, many people find their "sweet spot." On another hand, some of the "M" series valves have a much wider useable turns open range. It is like there is a slight difference in the machining that isn't shown on the graphs and specs. This is what I mean by 'not making sense' mentioned above.

... I did make a deal with maknwar for a swagelok metering valve so when I get that one, I hope I'll be able to dial in the flow much easier. ...

maknwar should be able to fix you up. Do you know the model number of the valve that you are getting?

 

[tchavei]

Hi again

@gsjmia

Hmm... now I remembered... I didn't reduce the output pressure when I moved from the Up Aqua to the Sera Reactor. Its still at 28 psi. Ups...
The new reactor is nice. Now I wish I had a more powerful filter although this one should already be overkill for a 16gal tank (its a eheim ecco pro 130 - 500l/h... about 132gal/h). The only bugger is that "ticking like" back pressure that makes my bubble counter go berserk.

@Left C

Thank you for the extensive explanation. Things are much clearer now. I made the deal for a SS-SS2-A and I did check the graphs. I think it should be fine. Specially for a 16gal tank. I'm adding quite a bit of bps though but bubble counters can be very deceiving and no two are alike. Mine makes very small bubbles so now it seems that I'm adding something like 6bps. I might move to a bigger tank in a couple of years but never over 55 gal. Do you think that the S series is enough for that size?

Thank you very much once again

Best Regards

Tony