Please Advise - First Water Test Results!

[trellis]

Ok, I bit the bullet and did a 75% water change. There was still a trace of ammonia afterwards but certainly no more than 0.25. The fish seem quite happy - even the cory has had a bit of a wriggle about though has gone back to being sedentry. I shall leave it for a couple of days now I think - don't want to keep stressing them out! I am going away for the weekend though so will do another change before I go on Thurs night - how big should that be do you think - 10% or 25%???

Just remember that the danger of the ammonia and nitrite FAR outweighs any danger from stressing the fish during a water change (this phrase is something that waterdrop often says).

DON'T leave it a couple of days, because you don't need to worry about stressing the fish, as long as you are careful and sensible when doing your water changes. As waterdrop has previously said, if you have anything above 0 ammonia or nitrite, you need to do another water change asap (preferably now).

As for thursday night, you will need to do another 75% water change (or even larger if you get away with it). if you can arrange for someone to come in and change the water whilst you're away, that would be helpful otherwise your ammonia and nitrite levels may get quite high whilst you're away

Hi

Unfortunately my little cory died last Wednesday, so I did a big change then as he may have been dead several hours before I found him. To be honest he hadn't been looking happy since we got him - not sure if it was water issues that killed him or if he just wasn't a healthy specimine to start with. I did another 50% change on the Thursday night before I went away. When I got back tonight I tested and Ammonia was just over 0.25 though didn't look quite as dark as 0.5. Nitrite was about 1ppm and Nitrate about 40ppm so pretty bad! I did a 75% change immediately and have got nitrate down to about 10-20, Nitrite is 0 and ammonia is between 0 and 0.25 (it doesn't seem to come down to 0, not sure if it's my water?) I cleaned the gravel with the siphon whilst doing the water chanhed and seived out lots of dead bits of plant too so should be much healthier in there now. The tetras still seem ok thankfully - will be monitoring carefully from now on.

What do I need to be doing now to maintain the tank in terms of water changes?

 

[waterdrop]

It may have been the nitrite(NO2) of 1ppm that did the cory in (and/or weak specimen) as that's nearly always more deadly than ammonia. The ammonia oxidizing bacteria create 2.7ppm of nitrite for every 1ppm of ammonia they process, so nitrite can spike more quickly and unexpectedly, especially in smaller tanks I think.

An unplanned fish-in cyclng situation can be a grueling experience for any beginner. It can seem to just go on and on. Every time you feel you done the hard work of a big water change, one toxin or the other just creeps right back up on you and threatens to go over the 0.25ppm danger point. Good deep gravel-cleaning as the water goes out is still important, I feel, even if the substrate looks clean. Its not debris you're removing, its water than might have a slightly higher concentration (invisible) of NO3.

The end of a fish-in cycle is near when you can go two days without changing water and have zero ppm readings for both ammonia and nitrite(NO2,) at which point you can continue to watch, counting those two days as the first of your "qualifying week."

~~waterdrop~~

 

[trellis]

It may have been the nitrite(NO2) of 1ppm that did the cory in (and/or weak specimen) as that's nearly always more deadly than ammonia. The ammonia oxidizing bacteria create 2.7ppm of nitrite for every 1ppm of ammonia they process, so nitrite can spike more quickly and unexpectedly, especially in smaller tanks I think.

An unplanned fish-in cyclng situation can be a grueling experience for any beginner. It can seem to just go on and on. Every time you feel you done the hard work of a big water change, one toxin or the other just creeps right back up on you and threatens to go over the 0.25ppm danger point. Good deep gravel-cleaning as the water goes out is still important, I feel, even if the substrate looks clean. Its not debris you're removing, its water than might have a slightly higher concentration (invisible) of NO3.

The end of a fish-in cycle is near when you can go two days without changing water and have zero ppm readings for both ammonia and nitrite(NO2,) at which point you can continue to watch, counting those two days as the first of your "qualifying week."

~~waterdrop~~

Hmmm think I still have a way to go then. I did the 75-80% change on Monday when I got home from the weekend away, then did another 25% change on Wednesday. Tested tonight and ammonia was between 0 and 0.25ppm, Nitrite was nearing 1.0ppm and nitrate was about 20ppm. I have done an approx 50% change again tonight. Would I be better to be doing say 10% changes daily or 20-25% every 2 days at the moment? Thankfully my tetras seem pretty hardy and are hanging on in there. I have been cleaning the gravel with every change - loads of debris comes out, it's actually quite satisfying to see it being sucked up!

 

[waterdrop]

You're changing out way less water than OM47 or I would I'm afraid. WD

 

[OldMan47]

If you are reading 1 ppm of nitrite, you are not doing large enough water changes often enough. The highest value you should ever see is 0.25 ppm of nitrite. Any higher than that means your fish are having a hard time getting enough oxygen into their system for good health. Please look to doing more frequent or much larger water changes. The "larger" part matters quite a bit. If you have 1 ppm and do a 90% water change, in theory you have reduced the water to only containing 0.10 ppm. That gives your fish some breathing room before your next test. If you do only 50% changes once a day and keep measuring 0.50 ppm each time before the change, you have only reduced the concentration to a theoretical 0.25 ppm and by the time you test again it will be too high. I find that it is far better to do enormous changes and then merely measure until the next one is needed than to try to minimize the water changes and have the fish always in poor water quality.