Test Readings

Get help on those urgent fishkeeping problems!

Postby kian1977 » Fri Jul 06, 2007 6:49 pm


Sorry to butt in on this thread...

I'm just starting up my aquarium, I know I need to leave it a while before fish are introduced and then only introduce minimal. I've purchased the API 5 in 1 Aquarium Test Strips and have got the following results

GH 180 KH 180 pH 7.0 NO-2 0 NO-3 0

Can you tell me what all these mean, wheter the GH, KH and pH results are too high?


Posts: 1
Joined: Fri Jul 06, 2007 6:44 pm

Postby Angel Fish » Sun Jul 08, 2007 5:45 am

Kian, I've split your question from the other thread as I think it would get swamped and lost if kept where it was :)
All the advice I give is based on my own personal 30 years of experience.
Main TT Page
Diabetes Forum
User avatar
Angel Fish
Posts: 6239
Joined: Fri Jun 15, 2007 12:09 am
Location: Dartmoor, Devon

Postby krekra » Sun Jul 08, 2007 7:37 am

GH 180 KH 180 pH 7.0 NO-2 0 NO-3 0

Can you tell me what all these mean, wheter the GH, KH and pH results are too high?

Well as for what they mean....

this is your temporary hardness. it consists of your carbonate and bicarbonate. Its called temporary cause you can remove the carbonate through boiling. KH is basicly the buffering capacity of your water. The higher the KH the more buffering capacity and therefor the more stable the pH.

your permanent hardness consisits of metal ions and salts and things that cant be removed with boiling.

GH- It is often mistakenly refered to as the permanent hardness but it is not. GH is more a measure of your magnesium and calcium ions. There are other things like metal salts and such that add to your permanent hardness

GH, KH, and pH are all related and changes in one will effect the others

Your Values for GH and KH are fine. You have semi-hard water and so should have decent buffering(no wide swings in pH). Your pH of 7 is neutral and most community fish will do fine. There are exceptions to that rule though so reasearch your fish.

As for the others....the test strips dont measure ammonia which is unfortunate as you will need to be able to test for these. Its very important. consider getting a liquid reagent test kit like the API master kit.

NH4(amonia ions) and NH3(unionized free ammonia) are produced by your fish in the form of waste(poop and pee) Ammonia is very irritating to the skin, eyes, gill tissue, and GI tract. It is also one of the few chemicles in the body which can cross the blood/brain barrier. Any ammonia levels in your aquarium are toxic to your fish. Fortunatly there are bacteria that will alter this but until you have sufficient quantities of this bacteria your fish will suffer.

the first bacteria to show up in a cycling aquarium will convert the ammonia to nitrites

NO2 is the simbol for nitrites. these are really bad. nitrites will bind to the fishes hemoglobin and prevent it from carrying oxygen properly and your fish will either suffocate and die or suffer permanent organ injury. In a cycled aquarium this number should always be zero. There is a second type of bacteria that will detoxify the nitrites to nitrates.

NO3 is nitrates. They are much less toxic then ammonia and nitrites but at high levels they can be toxic and/or support algea growth. They should be kept below 40 ppm or less if possible. You do this with your regular water changes.

All these things are related to each other and effected by each other. For example :

-high PH shifts the ammonia to its unionized and more toxic form.

-Nitrites are less toxic in hard water

-Nitrates are more toxic at low pHs

-Very high ammonia levels can actually inhibit the bacterial growth.

-Temperature can alter bacterial growth and ammonia toxicity levels too.

So all in all these measurements are all dependent on a balance and your fishes health is effected if any one value swings out of proportion and messes with the total water chemistry. The way to keep things happy and healthy is to make sure your tank is cycled well, stock slowly., DO NOT OVERSTOCK, and test your water regularly and do water changes regularly.

Check out the section on cycling


As for your readings....you wont have any ammonia, nitrites or nitrates till you have an ammonia source so dont be fooled by the zero values. They will always be zeor if there is no regular ammonia source.

So before you add fish consider doing one of 3 things

1. a fishless cycle using an ammonia source like rotting prawns, neat ammonia or fish food

2. seeding your aquarium with the filter squeezings for someone elses tank

3. cloning your tank by running your filter on a n established tank for a few weeks so it can get colonized with bacteria.

If you dont do one of the above then your fish will get exposed to toxic levels of ammonia and nitrites and suffer or even die because of it. You can do a fish cycle but you will be testing twice a day and doing a ton of water changes.

thats a lot of info for now.....digest it and then post any new questions and we wil be happy to help.

remember there is a lot of cool stuff on the main site here


Karena :mrgreen:

Just because you can doesnt always mean you should!
User avatar
Posts: 3605
Joined: Thu Jun 14, 2007 6:12 pm
Location: Crownsville MD USA

Return to Help!

Who is online

Users browsing this forum: No registered users and 0 guests