Join Date: Jan 2012
Location: Hudson, Quebec, Canada
Changing a large percentage of the water will not cause too much harm. I change 90 gallons or 50% of my 180g tank weekly!
The issue could be a bacteria bloom, the substrate you are using or something you have added to the tank.
Bacteria blooms or free floating algae can last for weeks...
10g Fry / Hospital / QT tank (as needed)
75g Saltwater Reef, Ocellaris Clownfish, Lyretail Antias (baby), Lemon damsel, Longtail Fairy Wrasse, purple dottyback, snails, crabs and a few LPS corals.
220g Still sitting empty (come on Lottery I need the numbers to come up!)