Toxic water chemistry

[Essjay]

I haven't mentioned anything about how your ammonia and nitrite got high. You must have some filter bacteria or your nitrate level would be the same as your tap level. So why did your ammonia and nitrite go up? We need to find out so it doesn't happen again.

Did you do anything to the filter before the ammonia and nitrite appeared? Change the media or even the filter itself? Wash the media under the tap? A lot of the bacteria live in the filter media so changing it throws the bacteria away. And the chloramine or chlorine in tap water kills bacteria, particularly if the tank hasn't been running long.

Did you get any new fish? If so, how many fish were already in the tank and how many new fish did you add? There are only enough bacteria to 'eat' the ammonia from the fish currently in the tank. If a lot more fish are added at one go, the filter bacteria have to multiply to make more of them to 'eat' the ammonia made by the new fish. It can take a few days to catch up if a lot of new fish are added at once.

 

[Kazzaye]

Thank you I think it's over feeding. I halved what I gave them last few days and ammonia is going down. I'm using tap water as well because it was becoming a real chore. I haven't ever measured GH or kh . I'm wondering what a 0 kh means for freshwater tanks. Thank you all for your help

 

[Essjay]

The natural processes in a tank tend to make the water more acidic - that means the pH tends to get lower. Nitrate is acidic, as are a lot of the other things excreted by the fish. Most tap water contains some carbonates which react with acids and stop the pH dropping. KH is a measure of these carbonates. I have low KH at 3. But yours is even lower than that. At zero it means there is nothing to stop the water becoming more acidic.

Because I do have some KH, I can stop the pH falling by doing regular large water changes to replenish the KH as it gets used up. But your water won't do that, water changes just remove some of the acidic things.

I know that Byron has very soft water and low kH, so hopefully he can help you with this better than me.

 

[Kazzaye]

Just wondering if I should put in a carbon filter pad to my high ammonia tank- would this help? At the moment I have a nitrate removing pad

 

[Kazzaye]

Byron?

 

[Kazzaye]

Sorry having a senior moment. Thought Byron was my local aquarium guy and I thought how can you know that? Just had to backtrack

 

[Byron]

Your tap water is fine except for the high nitrate. I'll come back to this. GH at 60 is presumably 60 ppm (= mg/l) which equates to 3 dGH which is good for soft water fish species (you have soft water species). I would not mess with GH or KH or pH. As essjay explained, the pH will naturally lower as the water becomes acidic. This too is fine for the fish mentioned previously.

My tap water is even lower, near zero GH and zero KH, and I have tanks of soft water fish that are thriving. Do regular partial water changes of at least half the tank volume once a week. I do one 60% or so change every week. This will keep the pH from lowering too far. And do not overfeed.

Now to the nitrate. At 20 ppm, you are at the upper level that is recommended for all tropical fish. Nitrate will occur within the aquarium too, depending upon the fish load and feeding and water changes and live plants. The latter are very helpful, and even if just floating plants will be good.

As for dealing with the nitrate in the tap water, there are members here who have this issue so they can best advise. They may spot this thread, though it is getting long and sometimes things get missed. Abbeysdad is one member who has successfully dealt with nitrate, so you could send him a PM to comment.

Prime conditioner was mentioned in post #1. Do not use this as a "treatment." It is OK at water changes because it will immediately detoxify the nitrate in the tap water, but this is only temporary, about 36-48 hours. At that point, if nitrate is still present, it will revert back to the toxic form. Your plants may use some of it by then, but not likely much, and some bacteria will use a bit. But my point here is not to be adding Prime as some sort of water treatment, as they have detrimental effects too as you can be making things worse for the fish. Using the amount needed for the volume of fresh tap water added is all you should use at a water change.

Byron.