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How to kill algae with CO2

30K views 11 replies 8 participants last post by  Homer_Simpson  
#1 ·
Thats I have been reading about killing off algae with your CO2 system. I just wanted to know how much CO2 to increase in my tank would it take? And ideas on it would be great.
 
#5 ·
From my understanding Algae is a result of inconsistent C02 levels/light/ferts (algae is more adaptable than plants to propagate with inconsistent levels) I believe a more consistant C02 level will allow Plants to take in carbon on a more consistant basis thereby giving the plants the enviroment needed in which to use it (or at least compete with algae). Also believe that light is a huge factor in C02 level requirements. Low light = low level C02 requirements/ferts as High light= higher levels of C02 requirements/ferts. Ferts also play a part... how much??? I believe that depends on your lighting (I like EI dosing because it takes the specific fert levels out of my hands and simply gives the plants more than they need... thereby giving them "all they can eat"... I simply reset fert levels at the next WC). All things that I have read states that the more light you put into a tank the more carbon/ferts are required. Also after about 40 ppm of C02, I've read plants don't noticably utilize levels above that. I think thats why the 30 ppm C02 level is recommended (could be wrong... some one will set me straight if I am). Alot of folks seem to think that fish suffer with anything over 30 ppm... I have been running 40-50 ppm (my lighting dictates this level due to increased plant uptake) and My discus are doing fine, and are growing out great:icon_wink No undue stress at all...(remember no BIG C02 ppm swings) If you look at a dutch tank which use no C02... and they are algae free. That would suggest that its not a matter of simply adding C02.... but finding a balance of Light/Natural C02 levels/ferts. Get one of those things out of wack and Algae will result....

Troy
 
#10 ·
Out of my almost first year of having a planted tank, I've had every kind of algae all the time. But, I'm always changing things. I've never left my co2 level the same for more than 3 days. More algae? Crank it up! Fish breathing heavy? Turn it down. Bubble count is different from yesterday? Readjust daily! I have things automated, but with solenoid temp differences against basement temp differences, I never get a consistent bubble count. So I can attest to algae taking advantage of inconsistencies in my tank.
 
#11 ·
I do have to say that the algae that I do have a some driftwood that I have in there is pearling really nice though. I kind of enjoy the look of it how it is now just if I could keep it that way would be great. Its not to bad but not all of it is gone just that right balance.
 
#12 ·
I have a 2.5 gallon nano with 30 watts 6500K daylight compact fluorescent 30watts light, Seachem Fert Dosing of different nutrients tapered for 2.5 gallon, regular excel dosing, weekly 20-30% water changes, and DIY Yeast injection. Well I was always critical that these things would keep the tank algae free. Algae(mostly string, Blue Green Algae at one point, diatoms, green dust algae, etc.,) pretty much had their way with this tank for almost a 6 months. Plant growth was not an issue and the plants fluorished, but the tank looked butt ugly because of all the algae. I just persisted in doing what I was doing and the only real change that I made was changing my DIY c02 brew weekly to try and create more consistent c02 levels as per Tom Barr's recommendation. Well, I don't know if the tank matured to the point where a balance was achieved or just changing the DIY C02 brew weekly caused the algae to disappear, or perhaps it was the barley straw extract I began adding with every water change, or a combination of these things. The tank is now 90% algae free. I was waiting for some plant anchors as I really need to rescape the tank due to the heavy jungle like growth. Depending on how the rescaping turns out, I may post pictures.

Now, I am hoping for the same miracle on a 5 gallon hex tank that seems to be over-run with green dust algae and has been for almost 4 months. With the 5 gallon hex I am experimenting with E.I instead of Seachem Fert dosing for comparison purposes, so we'll see how that goes.

Also, my "LostWorld" experimental tank as per my signature still remains 99% algae free and this was the tank that never ended up with a major algae break after 2 months like the other ones, and when I started that tank I was not using c02 injection or even excel. The only real difference between this one and the others is that it has a UV sterilizer and a purigan filter insert. But then, so does my 40 gallon tank, which is totally over-run with all kinds of algae. Go figure.