fish_newbie

I've been reading a lot and know that ammonia and nitrite always have to be 0 PPM in a healthy aquarium. But I am not sure what is the safe and healthy level of nitrate. Thanks

Lucy

Preferably 5-10 but as long as it's under 20 your fish should be ok.

fish_newbie

Thanks. And I forgot to ask what is the level of ammonia and nitrite are before it start killing your fish. My friend's aquarium had a mass extinction, he tested his water and ammonia was 0.2ppm.

Lucy

There's a lot of variables in that question.
Any amount of ammonia or nitrite is toxic.
Some fish are hardier than others, not that ammonia is any less toxic, but some can fight the effects better.
Weak fish will succumb quicker than healthier fish.
Length of exposure can also play a part.

ZomZom

The hosts of Pet Fish Talk recommend keeping nitrate at about 40-50 ppm. The reason (as best I understand) is that bacteria will begin to oxidise sulphates if there aren't enough nitrates for them, resulting in toxic sulfides. A rotten egg smell (hydrogen sulfide gas) is a sign that you have a sulfide problem.

Lucy

Been looking ( lol listening) over the site. So far I haven't found where they say that. Could you post the link to where this is mentioned?

I try to keep my nitrate between 5-10 and haven't had any problems.
Nitrate is a by product of nitrite..basically it's waste.
In a heavily planted fully cycled tank it's possible to have 0 nitrate (the plants use the nitrate) so if what you say was true bacteria woun't be able to live in a heavily planted tank where no nitrates are present.

Edit: never mind I found it:
denitrification
I see they mention that they felt that amount of nitrate might be good for the system shown.
Most of our home aquariums don't use that type of system.
Interesting stuff though, haven't had a chance to listen to that part, but I will later.
I only know what works for my 6 tanks.

ZomZom

Good job finding that page, I should have dug around and made a link to it in my post.

Whether what they say is true or not I have no idea, I merely mention it as another source of information. I agree that whatever has worked in the past is what you should probably keep doing.

Shawnie

IMO, its an owners decision on the nitrates...API recommends anything under 40 is good...I prefer anything under 20 and as lucy said, she likes her 5-10...over 40 to me, is like never flushing your toilet but still trying to live in your bathroom

Lucy

I was reading an article at the Kordon website and found this:
Edit:
Just to add I'm convinced you can find anything on the web to support whatever therory you have. Whether it pertains to fish or not. lol.

MissMTS

Lots of interesting links I agree with Lucy.... you can pretty much find anything on the internet to justify any oppinion. I keep my nitrates between 5-10 except on my African Cichlid Tank where higher nitrates are normal since overstocking is necessary (mine never get over 20 though). Generally, with regular weekly water changes, unless you are overstocked or are stocking fish with huge bioloads, there shouldn't really be a reason for nitrates to get over 10ppm. That's just my