<Sigh> How long to lower Nitrate?

[stu96ss]

Well I would like to thank all those who replied to my last post (why are my plants turning brown) Now I am tring to lower my nitrates. They are over 200 ppm. I have done 2 water changes (30 gal on a 100 gal tank) and even bought a nitrate remover. Still they are high. Both water changes have been 2 days apart.

Any other tips or ideas?

Thanks
Stu

[digger]

Check the nitrate level in your tap water. If the tap water has high nitrates, doing water changes isn't going to help. It's unlikely the high nitrates are killing your plants, but they could be harmful to your fish.

[Saluki]

Have you tested your tap water for nitrates?

If your tap water contains nitrates, it will take longer to lower the nitrates in your tank. It will also act as a lower limit for your nitrate concentration if you do not mix in RO or distilled water. If your tap water does not contain nitrates, just keep up the frequent water changes. They will come down. It is best not to change the concentrations too rapidly anyway. The fish do not tolerate rapid changes in water quality well.

If you do a 30% change, you should expect to see your nitrate concentration go down by about 30% (unless there are nitrates in the tap water). If it does not, then your tank is either way overstocked with fish, or you have something in the tank that is replenishing nitrates as you remove them. This might be fish waste burried in the substrate, some uneaten food somewhere in the tank, or the body of a dead fish.

[Wasserpest]

Funny, my problem is that all my tests show zero nitrates…

First you need to insure that your test kit is correct. Check your tap water and see what you get. Check some distilled water and see what you get.

You could also have your tank water tested at a fish store.

If you get correct values (between 0 and 30 ppm for tap water, 0 for distilled water? not sure if my assumption is correct here) and you know your kit is good, next you need to find out where all the NO3 is coming from. I don't think a few decaying plants would cause that...

But first see if your testing works.

[Wasserpest]

Ooopsie... I am typing way too slowly.

[stu96ss]

I tested the tap water and it is: Nitrates 0 Nitrite 0 Hardness 120 Alkalinity 90 PH 6.8

[Saluki]

My guess is that your nitrates were higher than what your kit is capable of reading. My kit only goes up to 160 ppm. If this is the case, it might take several water changes to get them down to readable levels.

Just keep doing your 30% changes each day. Also, make sure to vac every part of the substrate to make sure there isnt anything decaying in there. Good luck and keep us posted. I am currently fighting phosphates that are above the reading limit of my phosphate kit. Needless to say, I have also been fighting with algae.

[Ray1214]

If it says zero, I would really check my test kit.
First (and forgive me if I didn't read close enough), how are your fish doing. IF they look really stressed and you have some dying, then your nitrates are probably that high. (I myself have nver hit over 100 ppm unless cycling a tank). I think Ammo Lock will also lessen the effect of nitrates and ammonia on fish, however your test kit readings won't show it.
Second, Look for debris, and/or a dead snail or fish or shrimp, etc. That is usually a dead giveaway (pardon the pun) for your nitrates rising up that high. Try vaccuuming your substrate during your water changes to see if trapped food or trapped critter bodies are what is the problem.
Third, check your test kit. sometimes out of date chemicals or contaimanted kits will give really weird readings. boy I have had a Red Sea Nitrate kit spin me for loops one time becasue of expired reagents.
Ray

[Wasserpest]

If you are using the multi-test paper strips... perhaps you want to invest into a better test kit.