is changing water in my tank weekly too much, taking 15 g`s out of a 120 g?

Answer 1

It's a myth that changing the water too often will kill bacteria or harm the fish. The only way this is possible is if you changed the water every day and didn't allow any ammonia into the water.

By doing weekly water changes you are offering your fish fresh, clean water on a regular basis - something any responsible aquarist should be doing. Really - can the water be too clean for the fish? I replace about a third of the water every week, sometimes twice per week if I feel up to it - you can replace up to 40 gallons per week safely.

Answer 2

Twenty five gallons would be better. Just make sure that the replacement water is dechlorinated before adding it to the tank. Also see that the water temps are very close to the same.The only things that will harm the bacteria colonies are chlorinated water,sudden temperature changes and lack of Oxygen in the water. The frequency of water changes is largely dependent on the Bio-load (how many fish,and how dirty they are),and the type of filtration you have(and how frequently the filters are cleaned). Filters only get the "stuff" out of sight,the crap is still in the tank,and still in contact with the fish's water. Hope this helps.----Good luck.----PeeTee

Answer 3

That's about 12% a week, shouldn't be any problem.

Is this an established tank? If you have no problems with the water quality, you shouldn't need to do weekly water changes. Of course, 10 % a week is not too stressful for the fish and they do get used to the process that way. In a healthy established tank, the usual water change is about 20% once a month.

Thank you for caring about the well being of your fish.

Answer 4

Well, rule of thumb is to change water weekly if possible to bi weekly. Usually the amount is 20% from where the current water line is at which is usually two to three inches. Hope that helps.

Answer 5

For the different kind kind of fish ,you can use water accordingly because there are variety of fish which will be in different environment.For Example if u are having chiclids,guppies or other fresh water fishes variety u can use direct fresh water. Or if u are having variety like hybrid breed like parrot, arowna, some lionhead golden fishes u can can ask your nearest retailer or where u purchased fish Tips: To avoid the black spots and other infection add 1 gram of salt in fresh water ,it will avoid the fresh water little insects and bacteria (very little amount 1/2 table spoon)

Answer 6

well some might say yes. but I say no.
I have a 125gal and I change 20 gals a week and half 1 time a month. but i have 8 red belly piranha that are about 7inches so with them eating and there wast I have to to keep my water good.
I also think with river fish its good to change water more often than with lake fish. I think youll be fine

Answer 7

Once a week is fine, 20-25% of water is good! So you are doing fine!

Answer 8

you should actually be doing double that, 120g tank, taking out 25% a week, you should take out 30 gallons.