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~Col~
07-10-2010, 05:32 AM
Hi Everyone

This may seem like a silly question, but how long after a water change (approx 25% in a 4 ft tank) should I test the water. I realise I should give it some time to circulate through the tank/filter, but I'm unsure how long.

The filter I'm using at the moment is a touch too small, the gasket seal disintegrated on my Eheim Pro 2224 so I've had to order a new one (noone seems to stock them around here). So I'm using my smaller one (Fluval 204) and to help I've also got two airstones going to help circulate the water.

Water test yesterday was (I'm using a kit with test tubes and droppers):

Ammonia - less than 0.25
Nitrite 5.0
Nitrate just over 20
PH 7.2

Hence the water change. Am I doing the right thing? I haven't really had any problems with water qualtiy before so I'm at a bit of a loss.

Thanks for your help! :fish:

Cliff
07-10-2010, 05:52 AM
I would increase the water changes to at least 75% and complete every second or third day until your nitrite level drops to less than .5. It's VERY high right now and will start to effect your fish soon

With only a 204, I would wait one hour after a water change and then test again

~Col~
07-10-2010, 06:29 AM
Thanks Cliff!!

I'm wondering if I read the Nitrite wrong yesterday. The bars for 1.0 and 5.0 are very similar colours, just darker shading on the 5.0.

Today, after getting my husbands opinion on the colour match.

Ammonia - appears to be 0 or just over
Nitrite - 1.0
Nitrate - 40
PH - 7.4

The water's still a little cloudy, but not as bad as yesterday. I'll keep a close eye on it and do another water change tomorrow. Bigger depending on the results.

Ideally I know that Ammonia should be 0, Nitrite should be 0, Nitrate ? 20-40??, PH depends on the fish doesn't it?

Thanks again for your help!

FishGirl-Seattle
07-10-2010, 06:46 AM
If you are registering any nitrites and have fish in the tank you should do the water change now (75%). Cloudy water is not caused by nitrites or ammonia, and is usually not harmful to fish. Cloudy water could be algae, or substrate dust, sometimes even very small air bubbles. The fish killers (ammonia and nitrite) are clear. You can have crystal clear water and still have poisonous water chemistry, so never assume the clarity of your water is indicative of it's chemical state! Sorry to hear about your filter - I've read several posts tonight and it seems there is a rash of filter problems recently! Hope your luck improves in that regard!

jford21
07-12-2010, 06:03 AM
If you are registering any nitrites and have fish in the tank you should do the water change now (75%). Cloudy water is not caused by nitrites or ammonia, and is usually not harmful to fish. Cloudy water could be algae, or substrate dust, sometimes even very small air bubbles. The fish killers (ammonia and nitrite) are clear. You can have crystal clear water and still have poisonous water chemistry, so never assume the clarity of your water is indicative of it's chemical state! Sorry to hear about your filter - I've read several posts tonight and it seems there is a rash of filter problems recently! Hope your luck improves in that regard!


You made a great point about the water being crystal clear and your reading can be very bad such as ammonia and nitrites. My tank looks beautiful as far as the water quality, but my nitrites are not good. :scry:

~Col~
07-12-2010, 09:14 AM
Thanks for that!

Todays test:

Ammonia - 0
Nitrite - 0.5
Nitrate - 20
PH - 7.2

I've lost one serpae tetra this morning, although it appeared to have been attacked, it couldn't even open it's mouth to feed, it was dead a short time later. All the other fish are looking very happy and healthy.

I'll do another water change tomorrow. Fingers crossed it's working!

Thanks again for your replies!!

jford21
07-12-2010, 02:19 PM
Thanks for that!

Todays test:

Ammonia - 0
Nitrite - 0.5
Nitrate - 20
PH - 7.2

I've lost one serpae tetra this morning, although it appeared to have been attacked, it couldn't even open it's mouth to feed, it was dead a short time later. All the other fish are looking very happy and healthy.

I'll do another water change tomorrow. Fingers crossed it's working!

Thanks again for your replies!!


HOw many water changes did you do to get the Nitrites down? And what percentage? I have the same problem right now :ssuprised:

Yourkisa
07-12-2010, 02:46 PM
Im using the Api freshwater Liquid test and a while back I ran into the same issues that you both were. There is one thing that it took me a little while to cotton onto, but I belive that the strips can only register from 0.0 - 5.0 even though in effect your nitrites may actually be higher than that, it 'pegs out' at 5.0 and is unable to display any higher.

I came to this conclusion when i was cycling some filters on a smaller tank using a fishless cycle ( I also learnt my lesson the hard way first time round (blush) ) just to test a theory.
The nitrites were showing 5.0 on the scale and I did a 50pct water change, expecting the Nitrite level to drop to 2.5ish. They dropped to 4.0 on the scale, making me belive that I had in effect a level of about 8.0 to start with.

The way that this works is that whatever water change percentage you do, is taking away that percentage of the Ammo, Nitrites and Nitrates in the water, so its always better to do a large water change then several smaller ones. My maths skills arnt the greatest in the world but ill try to explain :-)
If you have 5.0 on the scale and do a 10pct water change, you will take it down to 4.5, (10pct of 5.0 is 0.5) if you do another 10pct water change you will only take out 0.45 this time round (10pct of 4.5 is 0.45).
This way, if you take out 50pct of the water in 5 lots of 10pct changes you only actually take the level down from 5.0 to 3.04. Each smaller water change takes less and less of the bad stuff out.

If you started off with a 50pct water change from a Nitrite level of 5.0, you would already, in one go, be down to 2.5.
I know that its a bit long winded there, but I wanted to put in the method to the madness !

(TLDR)
For water changes with high Ammonia and Nitrites : Go big, or go home.
Even small ammounts of Nitrites in the water is not good ( but im betting youve heard this one before :-) )

jford21
07-12-2010, 03:30 PM
Im using the Api freshwater Liquid test and a while back I ran into the same issues that you both were. There is one thing that it took me a little while to cotton onto, but I belive that the strips can only register from 0.0 - 5.0 even though in effect your nitrites may actually be higher than that, it 'pegs out' at 5.0 and is unable to display any higher.

I came to this conclusion when i was cycling some filters on a smaller tank using a fishless cycle ( I also learnt my lesson the hard way first time round (blush) ) just to test a theory.
The nitrites were showing 5.0 on the scale and I did a 50pct water change, expecting the Nitrite level to drop to 2.5ish. They dropped to 4.0 on the scale, making me belive that I had in effect a level of about 8.0 to start with.

The way that this works is that whatever water change percentage you do, is taking away that percentage of the Ammo, Nitrites and Nitrates in the water, so its always better to do a large water change then several smaller ones. My maths skills arnt the greatest in the world but ill try to explain :-)
If you have 5.0 on the scale and do a 10pct water change, you will take it down to 4.5, (10pct of 5.0 is 0.5) if you do another 10pct water change you will only take out 0.45 this time round (10pct of 4.5 is 0.45).
This way, if you take out 50pct of the water in 5 lots of 10pct changes you only actually take the level down from 5.0 to 3.04. Each smaller water change takes less and less of the bad stuff out.

If you started off with a 50pct water change from a Nitrite level of 5.0, you would already, in one go, be down to 2.5.
I know that its a bit long winded there, but I wanted to put in the method to the madness !

(TLDR)
For water changes with high Ammonia and Nitrites : Go big, or go home.
Even small ammounts of Nitrites in the water is not good ( but im betting youve heard this one before :-) )


Sorry if If it seems I'm highjacking this thread (blush) ....Thanks for the breakdown, I will also do a 50% water change and see what that gives me. I currently have a thread open on this subject so I will update my results in there. Thanks again!

~Col~
07-13-2010, 03:36 AM
Yourkisa - thanks so much for that info. I'll definitely keep that in mind when testing and doing water changes in future.

jford21 - I did two small changes (25% ea) and a larger one (50%). Which makes me believe that I was reading the test results wrong to start with as those changes wouldn't have brought it down as much as it did.

Thanks again!

jford21
07-13-2010, 03:43 PM
Yourkisa - thanks so much for that info. I'll definitely keep that in mind when testing and doing water changes in future.

jford21 - I did two small changes (25% ea) and a larger one (50%). Which makes me believe that I was reading the test results wrong to start with as those changes wouldn't have brought it down as much as it did.

Thanks again!


Thanks CoI for the info :22:

Glad to hear your levels are starting to look better; Good Job!