What is an acceptable Ph for tank? I'm about to transfer my Ryukin from a 2 gallon (SHAME!) to a 12(ish) gallon tank and I am comparing the Ph's. They are about the same (the tank the fish is in now has a Ph of about 7.3 and the tank it's going into is about 7.4 or 7.5) I was wondering if those Ph's are at all healthy...

Those PH levels are fine and healthy for goldfish. In my opinion, 7.4-7.5 is perfect, but others may disagree. Goldfish can usually tolarate elevated PH levels as long as they are stable. My tanks usually run at 7.9 to 8 and my goldies are fine because the PH remains stable.

Yep, I agree. pH in the mid 7s is great. But like br553 said, STABILITY is the key. Make sure the pH of your tank and your tap water are very close, if not exact when doing water changes.

Congrats to you and your fish on the new tank!

I'll admit that my tap water is about 7.2 or so when I add it to tank water that is near 8. But anytime I test for PH, I always get the same reading of near 8. I'm guessing it's from the high Kh and GH already in the tapwater.

My tap water is 7.2 also and my tank is always at 7.6.

Bak2it suggested that the difference could be due to dissolved carbon dioxide in the tap water.

To find out if that is the case, you can leave a bucket of tap water out for 24 hours and run an airstone in it to agitate the water and release the carbon dioxide. Then test the pH.

I would think that with such a big difference in pH between your tap and your tank, you'd be better off doing several small water changes per week rather than one large one. Unless, of course, you try the bucket thing and the pH tests out at 8 or very close. Then you could just leave a bucket or 2 of water out overnight to get the pH to match (unless you have a very large tank . . . .).