Hihi Ridzwan... I m using Tunze TS24 (ie 2 X 6100 turbelle) for my 3 by 3 by 2.5
There is no hard n fast rule to choosing a wavemaker. It depends on what you intend to keep & then how you conifgure yr flow directions ... u'll need some trial & error to get the correct flow configuration for yr tank as every tank has a different setup in terms of rocks etc ... My errors caused my bubbles & hammer corals to literally hv their flesh torn away but the sunnies, cauliflowers, acros, montis, torch, galaxy. mushies, star polyps all doing very well ... alot hv to do with deflecting and playing the currents off rocks n glass