Is it possible my fish load is just too high to be algae free?

Whiskey

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Hello all!

I have persistent algae issues, mostly GDA but some BBA as well. My plants grow well! C02 is stable at 45PPM or so, the tank is dosed with EI. Nitrate levels are not out of control, but DOC may be.

I did an experiment where I changed the water 50% 3 times per week, instead of 1, syphoning each time. I dosed KNO3 and PO4 to keep levels the same, and saw a dramatic decrease in Algae.

My fish load is through the roof. 75G tank:
About 40 guppies (They bread like crazy)
8 Cardnels
3 Plecos
4 Discus
15 assorted tetras
4 or 5 zebras

Is it possible my fish load is just too high to maintain an algae free tank with high light?

Would low light with lots of easy plants like Java Fern, anubius, and crypt help to address the issue?

Thank you,
Whiskey
 

fablau

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Whiskey, how do you know you have 45ppm of Co2?

Also: how old is your tank? How heavily planted is your tank?

I don't think your fish load is so high to cause algae. I think we must focus on Co2, light and possibly DOC.
 

Whiskey

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fablau;126595 said:
Whiskey, how do you know you have 45ppm of Co2?

Also: how old is your tank? How heavily planted is your tank?

I don't think your fish load is so high to cause algae. I think we must focus on Co2, light and possibly DOC.

The tank is about 2 years old, up until recently it was packed with plants, most were fast growing stems.

I know it is at about 45PPM CO2 because of the PH drop from CO2 off to CO2 on. I see 1.1 in the tank, but it will actually swing further if the water is left out in a cup for a day or two.

That's kinda what I was thinking,.. that my DOC accumulates too fast because of all the fish. I know my source water is a bit high to start with and with the heavy fish load and not being able to siphon the florite everywhere it's got to build up.

Whiskey
 

fablau

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Whiskey;126598 said:
The tank is about 2 years old, up until recently it was packed with plants, most were fast growing stems.

I know it is at about 45PPM CO2 because of the PH drop from CO2 off to CO2 on. I see 1.1 in the tank, but it will actually swing further if the water is left out in a cup for a day or two.

That's kinda what I was thinking,.. that my DOC accumulates too fast because of all the fish. I know my source water is a bit high to start with and with the heavy fish load and not being able to siphon the florite everywhere it's got to build up.

Whiskey

Thanks for the information. This is an interesting case because your tank looks similar to mine:

1. 75gl
2. 4-5 years old
3. Had small algae around, exactly like you, persistent.... until I raised Co2 enough!

Yes, I bet you are experiencing my same problem: low Co2. My tap PH is 7.4, and so I used to have a PH drop of 1.2 which I thought was an indication of enough Co2... But wasn't enough! Do you know when I begun seeing algae disappearing and plants getting REALLY better? When I reached a PH drop of 1.65!!

As I said, my tap (or my completely degassed tank water) has PH 7.4, and now I get the PH down to 5.75 for plants to really thrive and no algae around. I use a huge amount of co2, over 100ml per minute with Tom's Co2/water displacement method. I am sure that the only alternative way for me would be to decrease light, that way I would probably need less Co2... And I am considering doing that...

But wait... Every tank is different. I have an oversized wet/dry filter, good surface agitation and a strong pump (Eheim compact 3000), so degassing is pretty high, hence a lot of Co2 needed.

If I were you, I'd try to increase Co2, a little every day, watching closely your fish, until you will really start seeing plants "waking up" and algae disappear! It really works that way.
 

Whiskey

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WOW that's allot of CO2.
I do have pretty strong flow in the tank, but I don't have the kind of surface agitation you describe. I did push it closer to 100PPM CO2 at one point, but at that point my fish seemed to start suffering so I backed it down to where I am now.

Interestingly, in my tank the greater amounts of CO2 did not seem to have an effect on plant growth. I think this is because I've already hit non limiting levels, so more CO2 is just not needed.

Whiskey
 

yme

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When I reached a PH drop of 1.65!!

that is a lot! Do you have a very low KH? would be informative to know :)

greets,

yme

- - - Updated - - -

When I reached a PH drop of 1.65!!

that is a lot! Do you have a very low KH? would be informative to know :)

greets,

yme
 

Gerryd

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Whiskey;126737 said:
WOW that's allot of CO2.
I do have pretty strong flow in the tank, but I don't have the kind of surface agitation you describe. I did push it closer to 100PPM CO2 at one point, but at that point my fish seemed to start suffering so I backed it down to where I am now.

Interestingly, in my tank the greater amounts of CO2 did not seem to have an effect on plant growth. I think this is because I've already hit non limiting levels, so more CO2 is just not needed.

Whiskey

Hi,

Don't forget the 02 side of c02.....

Higher levels of 02 will provide a bit of safety for fish/critters, but also ALLOWS FOR MORE C02...

So, I degas quickly due to high surface ripple and large wet/dry, so I have to add more c02 because of this.

I would try increasing your 02 and surface ripple. Then raise c02 and see if fish are okay or not. Give at least 3-4 days between increases to be safe.

This is what worked for me. I had reached the limits of c02 in relation to the 02 I had. When I had better 02, I was able to add more c02 w/o hurting fish/critters and plants responded favorably.

Takes awhile to hit that magic combination.

Hope this helps.

- - - Updated - - -

Whiskey;126737 said:
WOW that's allot of CO2.
I do have pretty strong flow in the tank, but I don't have the kind of surface agitation you describe. I did push it closer to 100PPM CO2 at one point, but at that point my fish seemed to start suffering so I backed it down to where I am now.

Interestingly, in my tank the greater amounts of CO2 did not seem to have an effect on plant growth. I think this is because I've already hit non limiting levels, so more CO2 is just not needed.

Whiskey

Hi,

Don't forget the 02 side of c02.....

Higher levels of 02 will provide a bit of safety for fish/critters, but also ALLOWS FOR MORE C02...

So, I degas quickly due to high surface ripple and large wet/dry, so I have to add more c02 because of this.

I would try increasing your 02 and surface ripple. Then raise c02 and see if fish are okay or not. Give at least 3-4 days between increases to be safe.

This is what worked for me. I had reached the limits of c02 in relation to the 02 I had. When I had better 02, I was able to add more c02 w/o hurting fish/critters and plants responded favorably.

Takes awhile to hit that magic combination.

Hope this helps.
 
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fablau

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Is it possible my fish load is just too high to be algae free?

yme;126769 said:
that is a lot! Do you have a very low KH? would be informative to know :)

greets,

yme

- - - Updated - - -



that is a lot! Do you have a very low KH? would be informative to know :)

greets,

yme


I have a pretty high KH 7. I think O2 must be really high in my tank, as Gerry said also above. Otherwise there wouldn't be an explanation why my critters are ok with so much co2 in the water.

But I can tell you: I am also surprised that I need so much co2 to see my plants doing well and keep algae under control.

I'll open a specific thread on this Co2 issue to discuss it more in detail.
 

yme

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I have a pretty high KH 7

ah.. that explains:

degassed (i.e. +/- 0.5 ppm CO2) water of KH 7 has a pH of 8.6
a drop of 1.65 in pH due to CO2 addition results in a pH of 6.95

KH 7 and pH 6.95 gives a CO2 level of 22.45.

of course, all calculated by a simple CO2 calculator with all its flaws (as we know)

greets,

yme

- - - Updated - - -

I have a pretty high KH 7

ah.. that explains:

degassed (i.e. +/- 0.5 ppm CO2) water of KH 7 has a pH of 8.6
a drop of 1.65 in pH due to CO2 addition results in a pH of 6.95

KH 7 and pH 6.95 gives a CO2 level of 22.45.

of course, all calculated by a simple CO2 calculator with all its flaws (as we know)

greets,

yme
 

Whiskey

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fablau;126718 said:
Thanks for the information. This is an interesting case because your tank looks similar to mine:

1. 75gl
2. 4-5 years old
3. Had small algae around, exactly like you, persistent.... until I raised Co2 enough!

Yes, I bet you are experiencing my same problem: low Co2. My tap PH is 7.4, and so I used to have a PH drop of 1.2 which I thought was an indication of enough Co2... But wasn't enough! Do you know when I begun seeing algae disappearing and plants getting REALLY better? When I reached a PH drop of 1.65!!

As I said, my tap (or my completely degassed tank water) has PH 7.4, and now I get the PH down to 5.75 for plants to really thrive and no algae around. I use a huge amount of co2, over 100ml per minute with Tom's Co2/water displacement method. I am sure that the only alternative way for me would be to decrease light, that way I would probably need less Co2... And I am considering doing that...

But wait... Every tank is different. I have an oversized wet/dry filter, good surface agitation and a strong pump (Eheim compact 3000), so degassing is pretty high, hence a lot of Co2 needed.

If I were you, I'd try to increase Co2, a little every day, watching closely your fish, until you will really start seeing plants "waking up" and algae disappear! It really works that way.

It strikes me that this is well over 400 PPM CO2!
Is it possible that your PH probe is out of calibration? Do you have fish in the tank?

I don't have a wet dry, I do have good surface agitation, but my temps are pretty high because I keep Discus so O2 is a bit more difficult for me. That may be why my fish started gasping before yours, but still,.. I was running at around 65PPM Co2 it seems, you are 7 times that. I have never even come close to pushing it that far.

Whiskey
 

fablau

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yme;126813 said:
ah.. that explains:

degassed (i.e. +/- 0.5 ppm CO2) water of KH 7 has a pH of 8.6
a drop of 1.65 in pH due to CO2 addition results in a pH of 6.95

KH 7 and pH 6.95 gives a CO2 level of 22.45.

of course, all calculated by a simple CO2 calculator with all its flaws (as we know)

greets,

yme

How do you know that degassed water with KH of 7 must have a PH of 8.6??! If I let my tank water degas naturally, inside a glass for example, overnight, after 24 hours gives me PH 7.4. Exactly like my tap. Which value is the right one?
 

fablau

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Whiskey;126817 said:
It strikes me that this is well over 400 PPM CO2!
Is it possible that your PH probe is out of calibration? Do you have fish in the tank?

I don't have a wet dry, I do have good surface agitation, but my temps are pretty high because I keep Discus so O2 is a bit more difficult for me. That may be why my fish started gasping before yours, but still,.. I was running at around 65PPM Co2 it seems, you are 7 times that. I have never even come close to pushing it that far.

Whiskey

Yes, I have just calibrated my PH probe a few days ago, I do it every month. I use an Apex controller, so I am confident what I get is right.

And yes, I do have fish and critters, a lot! And they are fine. I see fish with a little accelerated respiration at the end of the day, but they never gasp at the surface.

I am really puzzled too! And I'd really like to know how much ppm of co2 I actually have. I don't rely on a drop checker, despite it would give me a yellow measurement, and I can't use the co2/KH table because according to it I would have so much co2 to kill fish instantly.... So what??! The only thing I know for sure is:

1. If I lower my co2, plants get worse and I get algae.

2. Fish and critters are ok.

But yet, I am trying to understand why some ADA tanks use so low co2 and plants do well:

http://www.barrreport.com/showthread.php?t=15733
 
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yme

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How do you know that degassed water with KH of 7 must have a PH of 8.6??! If I let my tank water degas naturally, inside a glass for example, overnight, after 24 hours gives me PH 7.4. Exactly like my tap. Which value is the right one?

the equilibrium between water and air results in 0.5 ppm CO2 in the water. the co2 calculator then gives pH 8.6 with a KH 7. And as I mentioned, we all know the flaws of such calculators... so please take it with a grain of salt.

btw: a glass has a relative small surface, the degassing might not be very efficient (don't know for sure, never tested it, but I can imagine it)

greets,

yme

- - - Updated - - -

How do you know that degassed water with KH of 7 must have a PH of 8.6??! If I let my tank water degas naturally, inside a glass for example, overnight, after 24 hours gives me PH 7.4. Exactly like my tap. Which value is the right one?

the equilibrium between water and air results in 0.5 ppm CO2 in the water. the co2 calculator then gives pH 8.6 with a KH 7. And as I mentioned, we all know the flaws of such calculators... so please take it with a grain of salt.

btw: a glass has a relative small surface, the degassing might not be very efficient (don't know for sure, never tested it, but I can imagine it)

greets,

yme
 

yme

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well...

I always found the articles from late Ariaan Briene very interesting. But... they are in dutch... perhaps google translate?
there are multiple articles on the site...


greets,

yme

- - - Updated - - -

well...

I always found the articles from late Ariaan Briene very interesting. But... they are in dutch... perhaps google translate?
there are multiple articles on the site...

http://www.hobbykwekers.nl/artikelen/aquarius-tubanti/co2/1936-co2-en-het-natuurlijk-evenwicht

greets,

yme
 

fablau

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Fascinating articles indeed! Thank you for the Lin. Unfortunately Google translate messes up things a lot, but the concepts can be understood anyway.

The calculator they provide gives me over 240ppm of Co2, which I doubt is correct.... Whereas the following one I found on Google:

http://www.fishfriend.com/aquarium_co2_calculator.html

Gives me around 21ppm which Sounds more real, even though I am pumping so much Co2 that I expected more... Which one is more correct? Thoughts?
 
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ltb420

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PH and KH are directly related so in order for the calculator to give you the correct value you have to be absolutely sure about your KH value. Fab, the calculator you found on Google gives me over 39ppm of CO2.
 

fablau

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Is it possible my fish load is just too high to be algae free?

Did you get 39ppm with my parameters? PH 5.75 and KH 7? That is my reached PH with my Co2 injection (PH 7.4 when degasses completely). I get 20.91ppm with the above parameters...