Rate of nitrate drop when nutrients are sufficient?

[PeterGwee]

Hi gurus and newbies out there...would like to know if any of you guys measure how much nitrate is used up or consume by your plants (rate of consumption) provided all your nutrients are in place (no nutrient deficiency) ? I was wondering how come my nitrate level keeps rising instead of dropping as I believe the micros are settled by JBL ferropol while I dose equilibrium to supplement K, Mg and Ca....which probably leaves me PO4 (never test it yet) . Nitrate is at 40ppm after only 2 or 3 days...now keep changing water to keep it low...getting tired man...arghhh...

[vinz]

Check your CO2 (via KH and pH) and PO4 levels. Try raising your CO2 to 30ppm. Your PO4 should be 1 or 2 ppm.

If you're not getting algae and fishes appear ok, don't change the water so often. Most fishes can take up to 200ppm NO3 before it becomes a worry.

[PeterGwee]

Vinz..I do have some BBA and spot algae problems which is why I am trying to bring down the nitrate levels. ...pH is 6.8 and KH is 3 when bubble rate is at 0.5 bps but today I try upping the CO2 and the pH drop to 6.5 giving me CO2 level of about 28.46ppm.

[sherchoo]

May I suggest checking your PO4, which I think is the main cause of BBA. I had BBA even with low NO3.

At the moment my 4ft is still with no BBA and the NO3 is 40ppm. Trying to bring it down with 20ppm dossage of K per week.
Not sure if this method works.

[hoppinghippo]

peter, have you checked your Fe levels? cuz ferropol has quite a bit of Fe. outer cap full for my 70-80L tank gives me 0.1 Fe. maybe that's the reason for spot algae? I get lots of spot when I overdose ferropol.

Sidepoint, is there any fert which contains Mg but not K or Fe cuz I want to dose Mg only?

[PeterGwee]

Hoppinghippo, the cause of algae to my knowledge is usually caused by too much nitrate or phosphate..Fe might not be that much of a factor unless is on the extreme side which I am not at..(me within 0.2ppm)

For Mg only fert..you can get MgSO4 from Dr. Mallick...but do take note that you need to balance it with amount of Fe or one might limit the uptake of the other nutrient.

[sherchoo]

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On 2/10/2003 12:19:40 AM

Sidepoint, is there any fert which contains Mg but not K or Fe cuz I want to dose Mg only?
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The only thing I can think of is Dr. Mallick's Magnesium Sulphate

[bclee]

Peter, IMO, if all else seemed in place, high NO3 may be just simply be oversupply of N from:

1. Root tabs with N-P-K
2. High bioload
3. Over feeding

In my case, it always happen when I add too many root tabs.

KH 3 and pH 6.5 looks good. It should slow down the BBA.

BC

[vinz]

Looks like CO2 was the limiting nutrient. If nothing else is limiting it, your NO3 should start to drop. Try one thing at a time. If you change too many things at a time, you might make things worst and not figure out what was wrong in the first place.

Give the plants and algae some time to react to the new CO2 levels. Meanwhile, check your NO3 every few days to see if it starts to drop. Physical removal of the algae will help hasten things a bit.

[tawauboy]

you can try to reduce no3 by
1) reducing feeding to once every 3-4 days.
2) add frogbits and/or other floating plants.
3) don't add any root tabs for time being.

how frequently do you need to trim your plants? and how much plant material do you remove each time you trim?
if you remove a reasonable amount of plant material every week, then chances of some nutrient deficiency is minimal.