Wednesday, September 14, 2011

How much water to change for fish tank?

Hi, I got a fish tank just about a month ago.

It's 38 to 40 gallons. I'm wondering how much water I should change in the tank.

I know I'm not suppose to change the entire water otherwise I'll shock the fish.

So, if anyone could please help me. would be much appreciated. thanksHow much water to change for fish tank?
Other than telling you how much... which all tanks are different and no one can tell you what's right for YOUR tank.... I'll tell you how to to determine for yourself.

First,hopefully you own a good test kit (even those notoriously inaccurate strips will work).

You ALWAYS want ammonia/nitrite 0 and nitrates 10 or less.As long as the ammonia/nitrite are 0,you are only concerned with keeping the nitrate down... one of the purposes of your water changes along with diluting concentrated solids and balancing pH.Those are the 3 reasons for water changes.

The first time you do a water change testing this way,take a nitrate reading BEFORE the water change and one about an hour AFTER the water change... start with the %26quot;standard%26quot; 25%.If you got into your target range (10 or less),good.25% is what you'd change... but if you didn't,you need to change more.

Ideally,by testing this way you should get to the point where your nitrates are at the top of your target range (10) right at the water change... and your change is dropping it lower.Once you have it timed out,you now know when and exactly how much to change so further testing isn't necessary unless you change stocking and/or filtration.

This way you may find out you need 10%,or maybe 30%.... or maybe 10% twice weekly.... whatever.The point is to maintain the water quality correctly for your set-up and not go off a %26quot;guesstimated%26quot; recommendationHow much water to change for fish tank?
I base it off of what is in the tank. But generally you can't do too much as long as you leave about half in there. Do maybe a third or a quarter every week or two weeks.How much water to change for fish tank?
Change 1/3 of the water, and don't forget to add Tap Water Conditioner when you put the new water in.How much water to change for fish tank?
20-25% on a weekly basis is adequate for most tanks.How much water to change for fish tank?
If it is well stocked 25% weekly should suffice.How much water to change for fish tank?