ok, It seems that my nitrates are a bit high, there running around 40. id really like to get them down to under 20. heres the problem, ive seen all different recommendations of how often you should change water in the tank. my GF is convinced that no more than once a month is sufficient. ive seen everything from that to 20 percent a week, to 15 percent every 2 weeks, etc etc. so what is the general recommended water changing interval and how much at a time. also how much is too much, ive seen people on here recommend 50 percent changes before, but ive also seen people that have said not to change more than 20 percent in a day or the fish will be stressed. also, can you change your water too much, what is the point where fish become stressed from changing water too much. I havent really gotten into a schedule for changing water yet, tank is fairly new, but I was thinking between 10-20 percent every 1 to 2 weeks. I also need to get the nitrates down, but, like I said I dont want to stress the fish with changing too often, if thats possible.
water changes, how much, how often, how much is too much
- Thread starter loki993
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I just picked up a tank that was supposed maintained once a month - the levels are off the chart. I am trying now to save the fish - going from such high levels to 'fresh' water is a big shock - it will take me hours to be able to put them in the tank again.
It only takes a few minutes to do it right.
I do a 25%-30% WC and gravel vac every week. Keeps the tank nice and clean and the levels safe.
It only takes a few minutes to do it right.
I do a 25%-30% WC and gravel vac every week. Keeps the tank nice and clean and the levels safe.
Remember, water changes do more than remove nitrates. They also remove other undesirable elements and replenish factors relative to maintaining pH.
I have tanks that get 50-75%, daily.
Routine is usually better than checking when an isolated component like nitrates get to a certain level.
Depending on your fish, quantity, filtration and food, I think 30% weekly is as little as anyone should go. Stability is the key.
I have tanks that get 50-75%, daily.
Routine is usually better than checking when an isolated component like nitrates get to a certain level.
Depending on your fish, quantity, filtration and food, I think 30% weekly is as little as anyone should go. Stability is the key.
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On an average we do 30 % twice a week on 3 tanks, including a gravel vac, witch may lead to a little more than 30 % ..If we notice slight fin damage, we'll do an additional 30 %....
I personally do 2 a week on all my tanks. I do one light vac with about a 20% water change. And then I do a heavy vac with about a 40% water change.IMO it does not stress the fish that bad. They actually get use to it. Mine are so use to it you have to shoo them out of the way of the gravel vac. Even if they do get stressed a little it is better for them to have clean water than let your water parameters get out of control.
im not talking about stressing the fish from the vac or siphoning, most of the time some of them get so close im a bit worried that they may get sucked in!!! my worry is the amount of water being changed, is there not good bacteria in the water that should be preserved and by changing too much you could remove too much of it??? I dont know.
Your beneficial bacteria is primarily attached to surfaces, so water changes shouldn't remove it.
There is almost no useful bacteria in the water itself. The bacteria live on hard surfaces whith the higest concentrations being where there is the best supply of food and oxygen0 normally the filter's bio- media. The next best place is in the upper level of the substrate and then on the deocr and even live plants if you have them.
Clean water is essential for fish health. Depending on the tank and what is in it, changes of anythwere from 30% a week for a lightly stocked planted tank, to daily changes of 50%, for young discus are common.
As long as the new water closely matches the tank water in terms of pH, gh and temp, you are OK doing almost any size change no matter how large.
My tyipcal change for most tanks is about 35-40%/week.
Clean water is essential for fish health. Depending on the tank and what is in it, changes of anythwere from 30% a week for a lightly stocked planted tank, to daily changes of 50%, for young discus are common.
As long as the new water closely matches the tank water in terms of pH, gh and temp, you are OK doing almost any size change no matter how large.
My tyipcal change for most tanks is about 35-40%/week.