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C02 stability and algae

1753 Views 7 Replies 5 Participants Last post by  Homer_Simpson
Hi all, new to the forum, i have a 20 gal. planted tank, probably about 6-7 months old, c02 injection, i think i'm sitting about 2.5-3 wpg for lighting, 2 filters (one bio-wheel the other just for flow) a and a powerhead.
I'm having re-occuring issues with bba, bga and random hair algea as well. i know im not dosing as regularly as i should on nutrients (trying to get better at it), and for now im not putting potassium in (due to algae growth) but im having a really difficult time keeping my c02 up to level. i've been checking with a drop checker and i can also tell just by the amount of algae growning that im not getting enough. seems as though it keeps fluctuating high then low for a while and then back to high again. i'm keeping the bubble counter filled and really am just frustrated at the fluctuation as it's causing so much algae growth.
anyone know of any way to try and steady out my c02? or overall how to just get rid of this algae by other methods? its making this whole hobby not so much fun.
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You can get more stable CO2 levels using pressurized CO2. You can also supplement with Excel (sometimes dosed directly on the algae) to help reduce the algae. Oh, it may help to decrease your photoperiod to try and "match" the amount of nutrients available to your plants.
what do you mean by 'match'? right now im running a 7 hour photoperiod, i could knock that down but i'd like to have some light on my tank so that i can see it and so that my fish are healthy. Is excell safe for extended use though? i was using it before, normal dosage and it really didnt seem to have that great of an effect...i'd like to find a somewhat perminant solution so that i can stop worrying about it and feel like i have a stable tank.
You need to find a balance between the lighting, the CO2, and the nutrients in order to have a stable tank. If one is lacking or one is in excess, you'll have more chance of algae growth. A 7 hour photoperiod seems about right though. Excel is safe for extended use. If you apply it directly on the algae, it also has an algaecidal? affect.
use two bottles linked together, and switch one out every two weeks. that makes the co2 output more consistent. i did that until i got pressurized. also, you should remove the biowheel on your filter, as it is outgassing co2.
I'm really hesitant to pull my biowheel out as it did wonders to get my tank set up in the first place. i'll be switching to a paludarium within the next 6 months anyway and thats a whole new set-up, just wanted to get some ideas now to keep everything going for the time being. the paludarium will be rethinking everything anyway...trying my best to start with some anti algae thoughts when building it. though i doubt it will be c02 injected.
for now im not putting potassium in (due to algae growth)
Don't worry about the potassium - phosphate maybe. Welcome to the forum:smile:!
IMHO, the biggest contributor to your algae issue is likely your irregular dosing of nutrients in addition to inconsistent c02. As others have mentioned that if these two are not in balance, algae thrives. One cause of Blue Green Algae, although not the only one and not the one in every case, is low or zero nitrates. Erythromycin treatment will kill it without harming your fish or filter but you still need to focus on prevention through regular water changes, nitrate dosing, increased circulation, etc., BBA is often caused by lack of or insufficient c02. Some people found spot treating it with Fluorish Excel kills it.
Here is a helpful list of causes of algae and solutions.

What is your plant density like? Having a lightly planted tank is a sure fire recipe for algae, IME. Also do you have any floating plants. You don't need to put in so many that it totally covers your tank surface and chokes out the surface and blocks out too much light, but a few floating plants can do wonders for algae control and you can always trim back the floating plants if they get too dense.

While prevention is always the best route, it does not hurt to have a good algae cleaning crew(Florida Flag fish/Rosy Barb/Black Molly, Oto Cats, amano/cherry shrimp, and perhaps a Bristlenose Pleco) to keep any algae to a bare minimum.

There is really no magic solution to preventing algae. I have failed in my efforts to find the Holy Grail of Algae Control. The closest thing to a holy grail of algae control is the following formula that I have found works time and time again.

High Plant Density(including fast growing stem plants and floating plants) + consistent 30 ppm C02(if high light but Excel suffices if low light, low maintenance tank) + a good fertilization dosing regime(Estimative Index for high light high tank with 50% water changes, but lean fert dosing for low light low maintenance with minimal water changes) + lighting intensity not in excess of 2.5 watts per gallon with a lighting duration not exceeding 8 hours but possible to do so using split photoperiod or noonburst + decent algae cleaning crew of fish = little or no algae. For some people, it is too much trouble to follow such a formula in which case I say focus on setting up a low light, low maintenance tank with low light plants and algae issues will become irrelevant. The trade off though is much slower plant growth.
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