Acid Production

[james_fish]

My PH levels in my tank are becoming quite acidic, so much so it is severely upsetting my mollies. My tetra's are fine. I have some PH neutral treatment but, the comeback is fighting strong and making the tank acidic again. What are the possible causes of this?

Thanks, James

 

[OldMan47]

The most common cause of the water becoming more acid the the build up of nitrates. Nitrates exist in an acidic form and will drive down the pH. You may need to do larger water changes each week than you have been doing.

 

[Mikaila31]

What oldman said and if your water has a low buffering capability. What is your tap pH vs tank pH? If you are doing regular water changes, not overfeeding, and don't have a ton of nitrates or any ammonia you shouldn't be seeing a pH change. If you are doing everything correctly and it is still happening then I would test the KH and GH so we can figure you waters buffering ability. That is its ability to resist pH changes. If it is low there are ways to increase it.

 

[waterdrop]

Agree with everything that's been said. If your tap pH is significantly higher than the the tank then your weekly water changes may just not be big enough and/or the gravel cleaning not deep and thorough enough. Good deep gravel cleaning and 50% weekly water changes can often keep a tank steady even if the KH is zero or one.

If you've already been doing this kind of weekly maintenance then, as said, it would benefit you to get a KH kit (or a KH/GH combined kit, as knowing the GH is also interesting, though not an action item like KH is.) With a KH kit you typically take a 5ml tank water sample and then begin to slowly drip the test reagent drops in, counting each drop carefully as you go. If your KH was 6 then the water would turn a certain color, such as blue, and then on the sixth drop it would suddenly change to another color, such as yellow. This indicates that the carbonate hardness (the KH) is six German degrees of hardness.

Water that has almost no carbonate hardness would turn yellow on the very first or second drop. drobbyb and I have written an article about this recently. Just find a recent post by drobbyb and I believe he has a link in his signature area to it.

~~waterdrop~~

 

[james_fish]

Okay, I'll do a big water change in the week, if the pH of the tap water is high should i treat it? If so what product is the best?


James

 

[drobbyb]

Yep, it's in my signature Some real good information there provided by FHM too.

 

[Mikaila31]

Okay, I'll do a big water change in the week, if the pH of the tap water is high should i treat it? If so what product is the best?


James

Depends how high. what is your tanks pH and what is your taps pH? Also what are you using to test it?

 

[OldMan47]

Unless the pH from the tap is very high, there is really no reason to try to lower it. Fish like a nice stable tank with a fairly constant mineral content in the water and a pH that doesn't move more than about a full point or two in a day. A change from say 6.5 to 8.5 is starting to get too big but smaller variations are well tolerated by most fish. In my high tech planted tanks, the pH goes from about 7.8 at night with no CO2 going in, to about 6.8 near the end of the day when the bottled CO2 has been running for several hours. The fish quite frankly ignore the change because they see the same kind of changes, for the same reason, in the wild. Lakes and streams are affected by sunlight to remove all available CO2 during the light phase and between sunset and dawn the plants and fish both push the CO2 in the water up and the pH down. We do things backward on a high tech planted tank, because we want the CO2 high when the plants can use it, but the swings are similar.