Aqua/\Man wrote:
I've kept a 75 gal for over a year now. It holds mostly small species
under 3 inches. I change out around 20 gallons every week. Some have
told me that I was changing too much water too often.

Should I curb the amount I'm changing?


All the fish appear fine, with a loss of a couple of cardinal tetras and
a swordtail over the course.

As long as you keep doing the same, no. It's not too much.
You would run into trouble if one week you did a 50%, then the next a
10% then waited a few weeks, did another 50%, etc.
When you keep it consistant, it's perfectly fine.
I've known long time hobbyists who do a 50% weekly, or more.
As long as you keep consistant, it's peachy.

Are you re-using filter media? By this I mean rinsing out filter pads
or sleeves in old tank water and then putting them back. This saves the
nitrifying bacteria on them.