When to dose with nitrate

[black udder]

ok... I have about 2wpg (96w for 46g tank) and I'm running DIY CO2. I seem to be getting a little hair algae - not a bunch, but a little.

Water params aren't totally out of whack - I think they're around Am 0, nitrite 0 , nitrate 10-20, phos. 1-2, last time I checked the CO2 was around 20ppm.

I get some natural light for part of the day which seems to be breeding some in the corner, but the otto's are doing well with that area.

I'd like to get some SAEs, but I need to get rid of some fish to make room for them... just wondering if perhaps I need to dose a little nitrate for the plants?

I have green light stump remover (potassium nitrate) if that would work.

Is it dangerous to just dose a small amount to see if it helps?

 

[BrianNY]

The green light is pure KNO3 so that will work. You don't want to dose anything too radically or it might be fatal to the fish. The thing is your nitrates look fine. I dose to keep mine in the 10 to 20 ppm range.

Your phosphates look to be on the high side and could be the cause of your algae probs.

 

[malkore]

Tell me more about your water changing routines first.
Secondly, are you dosing any potassium? Iron? trace mix?

Phosphate could be a little lower, but you could have either a K or trace deficiency, causing your plants to not take up the phosphate, or the nitrate. So adding nitrate could make things worse if it's a trace deficiency.

I've run my 75gal. at 20ppm NO3 and 2ppm PO4 for a few weeks and had no algae outbreak.

I recommend the SeaChem phosphate test kit, so you can know for sure if you have 1 or 2 ppm of phosphate, since it is a rather 'touchy' macronutrient.

 

[black udder]

will get some accurate #'s and post them. I have a tad (about 1ppm) of phosphate from the tap to start with.

I've added some flourish excel for the last two weeks - once a week and I change about 15% pwc once a week.

I've used the plant tabs - I think seachem - but they've been in the tank for a couple months at least.

I have a liquid phosphate test. I'll check to see what the seachem test is.

Thanks for the info guys - something to check. I know from all your other posts that something is a tad out of balance, but pinpointing it is the challenge!