I know I'm not the only person that deals with this problem and I'm curious how others deal with it. My water comes out of the tap with a ph of about 8.6 to 8.8 and lowers down to about 7.6 within 1-2 days. Do I have any other things I can do other then age the water in a seperate tub before a water change? I've tried tons of airstones and that doesn't make any immediate impact on the water. How much of a ph swing is ok on the fish during a water change?
Ph gasses off a lot and lowers quite a bit
- Thread starter Rayfinkle
- Start date
When you do a water change, how much water do you change?
Do you know the alkalinity of your tap water?
Sometimes pH can be high, with a low alkalinity.
If alkalinity is low, it means there may not be enough buffer in it to stabilize pH if the water change is not large enough.
Do you have a filter that hasn't been cleaned lately with a build up of mulm?
Do you know the alkalinity of your tap water?
Sometimes pH can be high, with a low alkalinity.
If alkalinity is low, it means there may not be enough buffer in it to stabilize pH if the water change is not large enough.
Do you have a filter that hasn't been cleaned lately with a build up of mulm?
Many species of fish have been tested to see if rapid pH swings are a problem. E.g., fish that evolved and lived in lakes with a pH of 8.5 were dropped directly into water with a pH of 5. Nothing remarkable happened.
Numerous species handle a very wide range of pH (5.0-9.5.) This doesn't mean every species will be as tolerant, but based upon studies I've seen, imo, in the range you described (8.8 to 7.6), it would unusual for a fish to be significantly affected.
Also, although much slower, it's normal in many large ponds for pH to swing up and down every 24 hours (due to photosynthesis and nitrification) along a relatively large range. This doesn't injure the fish or cause them to die.
Naturally this is not recommended for eggs or fry which are much more sensitive, but for adult fish in general it's not a problem.
Also, swings up in pH can be dangerous, not because the pH itself is a problem, and not because pH going up is a problem, but because some metals and chemicals (ammonia in particular), which might be tolerable or sublethal at low pH, can become more dangerous at higher pH levels.
As
duanes
pointed out, high pH water with low alkalinity can suffer from rapid pH declines. Water with good buffers will have more pH stability. It's definitely worth testing your water.
Numerous species handle a very wide range of pH (5.0-9.5.) This doesn't mean every species will be as tolerant, but based upon studies I've seen, imo, in the range you described (8.8 to 7.6), it would unusual for a fish to be significantly affected.
Also, although much slower, it's normal in many large ponds for pH to swing up and down every 24 hours (due to photosynthesis and nitrification) along a relatively large range. This doesn't injure the fish or cause them to die.
Naturally this is not recommended for eggs or fry which are much more sensitive, but for adult fish in general it's not a problem.
Also, swings up in pH can be dangerous, not because the pH itself is a problem, and not because pH going up is a problem, but because some metals and chemicals (ammonia in particular), which might be tolerable or sublethal at low pH, can become more dangerous at higher pH levels.
As
duanes
pointed out, high pH water with low alkalinity can suffer from rapid pH declines. Water with good buffers will have more pH stability. It's definitely worth testing your water.
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I change about 20-30% but ideally I would like to do 50% water changes but I don't want to shock the fish or anything.
Alkalinity of my tap water (from water companies website ) alkalinity (total) as CaCO3 -- 107 ppm.
And I keep my filters all pretty clean. I even set out a bucket of water out and in about 2 days it went from a 8.8 ph out of the tap down to a 7.6 and that was without aeration or anything.
Fresh water fish are constantly urinating, this drops the pH of the tank (urine=uric acid) over time.
If you change 50% of the tanks water, you remove half the urine.
When you replace that water, the pH of the replacement water may or may not drop depending on how alkaline the replacement water is.
To test for alkalinity a weak acid is dripped (titrated) into a sample, if alkalinity is high, the sample will absorb (or is it adsorb(?)) much more acid than low alkalinity water (with this action pH drops).
This is why to maintain a stable pH in aquariums, frequent, large, water changes are often needed.
And the more, and larger the fish in the tank, the more piss is created, so the more water changes are needed to dilute the piss soup the fish create.
If your alkalinity is 107ppm, it is similar to what I had in Milwaukee, and to keep my tanks stable with that amount of buffering, I did 30% water changes every other day.
I also used aragonite as a partial substrate, and on very over stocked tanks, ran fluidized bed reactors, using aragonite as media.
Also, the more frequent the water changes, the less pH fluctuation, so more water changes less shock.
If you only change water once per week, that will create more shock than more frequent changes.
If you change 50% of the tanks water, you remove half the urine.
When you replace that water, the pH of the replacement water may or may not drop depending on how alkaline the replacement water is.
To test for alkalinity a weak acid is dripped (titrated) into a sample, if alkalinity is high, the sample will absorb (or is it adsorb(?)) much more acid than low alkalinity water (with this action pH drops).
This is why to maintain a stable pH in aquariums, frequent, large, water changes are often needed.
And the more, and larger the fish in the tank, the more piss is created, so the more water changes are needed to dilute the piss soup the fish create.
If your alkalinity is 107ppm, it is similar to what I had in Milwaukee, and to keep my tanks stable with that amount of buffering, I did 30% water changes every other day.
I also used aragonite as a partial substrate, and on very over stocked tanks, ran fluidized bed reactors, using aragonite as media.
Also, the more frequent the water changes, the less pH fluctuation, so more water changes less shock.
If you only change water once per week, that will create more shock than more frequent changes.
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Sorry I should have been more specific. I do the 20-30% water changes 3 times a week. Should I bump it up to 50% water changes? Could I get away with 2 weekly 50% water changes?
I actually did a 50% water change last night on one of my 75s. I tested it before the water change and the ph was 7.6 and I tested it after and it brought it up to about 8.6. My tap water comes out of the faucet at about 8.6-8.8. I didn't expect it to raise the entire tank that much since I only changed 50% of the water. Idk this is all very frustrating.
Many species of fish have been tested to see if rapid pH swings are a problem. E.g., fish that evolved and lived in lakes with a pH of 8.5 were dropped directly into water with a pH of 5. Nothing remarkable happened.
Numerous species handle a very wide range of pH (5.0-9.5.) This doesn't mean every species will be as tolerant, but based upon studies I've seen, imo, in the range you described (8.8 to 7.6), it would unusual for a fish to be significantly affected.
Also, although much slower, it's normal in many large ponds for pH to swing up and down every 24 hours (due to photosynthesis and nitrification) along a relatively large range. This doesn't injure the fish or cause them to die.
Naturally this is not recommended for eggs or fry which are much more sensitive, but for adult fish in general it's not a problem.
Also, swings up in pH can be dangerous, not because the pH itself is a problem, and not because pH going up is a problem, but because some metals and chemicals (ammonia in particular), which might be tolerable or sublethal at low pH, can become more dangerous at higher pH levels.
As
Do you know if the ph swings have any kind of possible long term consequences or effect growth?
What kind of fish are you keeping?
I live near Lake Gatun in Panama, the lake fluctuates a pH range of 6-9 depending on rain (or lack of it) time of day, the seasons, and how much traffic passes thru the Panama Canal allowing sea water in and out.
Many Central American cichlids, tetras, live bearers, tarpon, and even introduced peacock bass live well under those conditions. Although the peacock bass don't get as large as in the softer waters of the Amazon.
I live near Lake Gatun in Panama, the lake fluctuates a pH range of 6-9 depending on rain (or lack of it) time of day, the seasons, and how much traffic passes thru the Panama Canal allowing sea water in and out.
Many Central American cichlids, tetras, live bearers, tarpon, and even introduced peacock bass live well under those conditions. Although the peacock bass don't get as large as in the softer waters of the Amazon.
Mainly cichlids ( Parachromis managuensis and flowerhorns). I also have a few types of bichirs. Just recently got rid of all my Africans.
Most Central American cichlids are riverine, which makes them very tolerant of pH swings, and other changing water conditions, rivers obviously fluctuate with different weather conditions, even if they occur hundreds of miles away in mountains. I can't speak to Bichers because I've never kept them.
When I had spawning P managuense, I'd sometimes add cool, low pH rain water to my normal 7.8 to 8.0 pH tank water, to mimimic seasonal changes in they might experience in nature, and get the spawning process in gear.
When I had spawning P managuense, I'd sometimes add cool, low pH rain water to my normal 7.8 to 8.0 pH tank water, to mimimic seasonal changes in they might experience in nature, and get the spawning process in gear.