Testing Water

[simpdaddy]

I wanted to know how often should I be testing my water levels?
I change 15 Gallons of water once a month and check it the next day to make sure everything is in sync. I'm going to be getting a calcium and alk test kit in the next week to begin testing those levels to get my coarlline to grow and add some soft corals.
My current test kit is for ph, ammonia, nitrite and nitrate. I didn't record the levels on paper when I did it but they were good according to what I've read in my test kit and on this board.

 

[simpdaddy]

I bought the tank from my friend who's had it for well over a year now.

 

[ajroc31]

I think you should change less water more frequently. 1/3 is alot. With lr, and sb, the 15 gallons is probably about 37% which is alot. How about 10 gallons every 3 weeks.