The Readings From Today

[MewMew42]

Okay so I haven't had my tanks for very very long and I'm just cycling my new one [fish in]

meanwhile my other 10 gallon, which is my first tank [when i didnt quite know what i was doing] had a spate of deaths [before that i had ordered a test kit, which i got today] now it's the fisrt time I have used the Api master test kit and I dont really know what the right readings should be
Am i right in thinking I should do water changes if the readings are above 0?
How soon after doing the change should I test again?
Please help I'd like to start doing this properly!

here are the readings:

PH 7.2
NitrIte 2
NitrAte 20
Ammonia 0

If theres anything I've forgotton please tell me!

 

[loachman]

NitrAte doesn't really matter. Keep it below 40-50ppm, although under 200 ppm is safe. The readings are somewhat inaccurate, and depend on how much you shake the vial and bottle of reagent. Shake like crazy.

NitrIte should be 0ppm. It is toxic. If you have fish in the tank and a nitrIte reading, you should do a water change to reduce this.

Ammonia should be 0 ppm. It is toxic, moreso than nitrIte. If you have fish in the tank and an ammonia reading, you should do a water change to reduce this.

pH should be rather stable, although you can see it swing 0.2 pH over the course of the day. A pH of 6.0-8.0 is fine for almost all common fish.

 

[MewMew42]

thanks a lot!

I was really confused between NitrAtes and NitrItes

yeah i found that it was quite hard to tell the difference between the colours on the chart!

thanks again!

 

[waterdrop]

Yes, just to throw another agreement in, I agree with all of loachman's excellent advice up there.

The goal in a fish-in cycling situation is to keep ammonia or nitrite(NO2) from going above 0.25ppm. Any trace of either toxin showing up is bad, but having it go higher than 0.25ppm and certainly at 1ppm, you are looking at an emergency for many species of fish (although technically, they do vary.)

With your new kit you can be a bit of a detective and figure out what percentage and frequency of water changes will allow you to dilute whichever toxin (nitrite(NO2) in your case) is showing up to be close to zero and to not rise above 0.25ppm by the next time you test and can perform another water change. For most people, the typical problem is not having it get above 0.25 before they can get home from work or before they get up the next morning.

When you get a result like NO2=1.0ppm, you want to immediately perform about a 50 to 70% water change (this assumes you have tested your tap water and its not bringing in ammonia, nitrite or nitrate itself.. that's good to test too) and then test again about a half hour later. If the first water change did not get you very close to zero then you can safely perform another large water change as soon as one hour after the first one. Usually this sort of "double change" only need be done once and then your testing will begin to show that you've got things under more control.

The problem with nitrite(NO2) is that is suffocates the fish. The NO2 molecules can attach to the fish blood hemoglobin in the same spots that oxygen would and when it does the result is "methemoglobin" which is implicated in "brown-blood disease," and since oxygen is not being carried by the hemoglobin, you've got suffocation with one of its very first symptoms being permanent nerve and brain damage in the fish.

~~waterdrop~~

 

[OldMan47]

Your retest question is easy and not so easy to answer. Depending on the circulation of water in the tank and how much you stir things up during a water change, you could retest after 10 minutes or an hour. The idea is to give the tank time to thoroughly mix the new and old water and then you can go ahead and retest. What you don't want to do is test, do a water change and then end up testing mostly new water or mostly old water. Either one will throw you off on deciding your next action.

 

[waterdrop]

Completely agree with that OM47 -- has always been a hard one to say and easy to see us giving answers from 10 minutes, 15, half hour all the way to an hour as you say, with no evidence behind any of it. The idea of a second large water change coming an hour after a previous one is more important when the toxic level that initiated it was pretty high (like 1ppm and above I'd venture) whereas there's less importance as you move down past 0.50 and 0.25 levels. I suppose in many ways, the better advice then would be to retest out near an hour to ensure better mixing, unless the level that started it all was extremely toxic, like 3 or 4ppm or something.

~~waterdrop~~