What are acceptable values for my nitrates and alk?

[Zebo]

Hi,
I just tested my water and ive got about 1.5meq/L of nitrates, and about 3 meq/L of alk, i cant test calcium yet because i dont have a test kit for it, which im going to buy today, but i didnt think id need to be dosing my b-ionic 2part chem because i dont have any corals yet. I see alot of alk in dkh but my test kit only tells meq/L what should the values im aiming for be? Can u show me the equation to go from meq/L to dkh? Thanks

[Randy Holmes-Farley]

I usually recommend 2.5-4 meq/L (7-11 dKH) for alkalinity, so yours is fine.

Here's an article on alkalinity:

http://www.advancedaquarist.com/issues/feb2002/chemistry.htm

I assume that your nitrate is 1.5 ppm, and that is a fine value. Lower is better, and less than 0.5 ppm is best, but 1.5 ppm is reasonable.

[Zebo]

Well thats good to find that my alk is good, but my Nitrates are at 1.5Meq/L, im fixing to do a water change, but where should my nitrates be at while having corals and such?
Thanks

[photobarry]

I doubt your test kit is showing nitrate in units of meq/L You wouldn't measure nitrate in meq/L for the following reason. The technical definition of an equivalent is the amount of substance it takes to combine with 1 mole of hydrogen ions. This measurement is generally used when trying to define the buffering capacity of a solution (such as Alkalinity). I would double check your test kit and see what's the unit of measure.

[Zebo]

DOH! I meant to say mg/L i have 1.5 mg/L of nitrates, what should my range be? Is mine to high? Where should it be to keep corals healthy?
Thanks
Lyle

[photobarry]

mg/L is conveniently the same as ppm.

[Zebo]

so at what nitrate levels should water be replaced?

[Lutefisk]

If you're doing things right your nitrates won't rise and if you do things better you should be able to lower them.

What are you doing for denitrification?

Deep sand bed, plenum, live rock, refugium, ...

Paul

[Zebo]

i thought nitrates usually rose until u did water changes? I have a 5" DSB, with 80 lbs of LR and a remora pro skimmer.

[Randy Holmes-Farley]

Water changes are one way (a poor way) to reduce nitrate. Growing macroalgae is a good way. Nevertheless, if your aquarium has 1.5 ppm nitrate, I would not be worrying about it. Many folks have reef aquaria that look just fine with nitrate at 15 ppm, some at 50 ppm.

Elevated nitrate does not hurt many organisms. Corals with zooxanthallae are one exception where it sometimes does hurt (because the zoox grow too fast for the host). Many tank inhabitants will likely grow faster at 1.5 ppn nitrate than at natural levels.

What kit are you using? Beware that some read in units of ppm nitrate nitrogen, and that is equivalent to 4.4 times as much nitrate ion.

[Zebo]

Thanks Randy,
I am using Seachem, i heard it was a pretty decent test kit.
Thanks
Lyle

[tanku]

hey randy, does the red sea test for nitrates measure the nitrate nitrogen?

[Randy Holmes-Farley]

I don't know what units Red Sea uses. If it doesn't say the word nitrogen in the description, it probably does not. Anyone have the kit to tell for sure?

I've not used the Seachem kit, but it reads in ppm nitrate:

http://www.seachem.com/en_support/kit_pdfs/0960.040-Nitrate.pdf