Nitrates D:

[Luzi]

Having just got my first test kit, I've found that my nitrates are at 100! I've just done a mammoth water change but I think my fish have been living in this for a long time. What do high nitrates cause? I have 2 orange platies with pale patches across their backs and dark scale edges which i think were caused by the nitrates. There's no strange gilling but they do ocassionally flick. Nitrites are at 0

 

[Equilibrium]

Having just got my first test kit, I've found that my nitrates are at 100! I've just done a mammoth water change but I think my fish have been living in this for a long time. What do high nitrates cause? I have 2 orange platies with pale patches across their backs and dark scale edges which i think were caused by the nitrates. There's no strange gilling but they do ocassionally flick. Nitrites are at 0

But right your tank is cycled coz nitrites are 0, Nitrates are formed from Nitrites via your filter. The only way to remove nitrates is to do water changes or add a special denitrifier to your filter that will absorb nitrates.

Did you know your tap water also contain Nitrates ? Nitrates are not as poisonous as Nitrites and so Fish can stand higher levels of Nitrate than they could Nitrites

 

[Luzi]

I know nitrates are less toxic, but levels of over 50 over time do harm fish, and since this is my first test kit i think they've been there for a while
Water change has brought them down to about 75, but i'll check tap water levels to see if they're similar

 

[spectrum]

I think high nitrate levels will have a similar effect to ammonia poisoning, gasping at the surface and eventually death. Obviously you need far more nitrate than ammonia to have that effect.

 

[Luzi]

My fish don't seem to be gasping or have strange gills... All of them are eating fine and act normally. Maybe nitrates weren't high enough for long enough to cause serious damage.
Would nitrate cause the pale patches?

 

[Assaye]

As far as I know 100 nitrates is actually still a safe level. When people say "oh, your nitrates shouldn't get above 20/40/60/etc" it tends to be a random stab in the dark because it seems sensible that low nirates = good.

You need to know what your tap water nitrates are - there is no point doing water changes to remove nitrates if you have very high tap water nitrate as well. If your tap water is lower then a series of large water changes (about 40%) over the next few days will lower it safely.

How big is your tank and what stock do you have? Also, how often do you normally do water changes? How much do you feed? High stock and few water changes will cause nitrates to climb fast and stay at higher levels.