My tank size is actually 48'x18'x18 ie 67g but to have more water volume I made a bio filter with another tank that is 36'x18'x18' and I keep it outside my sitting room. It sounds funny but it really works, wht I did was I made some fin inside that bio filter and filled one fin with live coral, next one with live sand, and the other one with PVC pipes of different sizes cut in to 2' pieces.
the next one is empty and then it will overflow to another barrel 21g and from that barrel water goes to my tank. Im actually having about 138g of water circulation. I dont have a skimmer that all filter system I have. To give areation I put an air stone into the barrel. Thats all. and none of my coral dies. I still didnt start keeping SPS coral cos I dont have that much knowledge.
I do water change every three weeks about 31g in three weeks. Thats pretty good. Lights, I have 2x Tritons, 1xBlue moon and an Actinic Blue thats all lightings I have.
What else. Aha Im proud to tell you this, Im from Maldives where you dont have to spend a dime to buy corals, u name any, u get it here. heheheh pretty cool. But poor me dont know anything about this water chemistry and stuff. If anyone wanna see my tanks send me and email to femunu@usa.com. Ill show u how it looks like. HELP me.