the best way

[artur]

Maybe that is stupid question but i ask anyway. I heard so many times that for proper gas exchange you should break the surface of water.So i set my return nozzle from sump to tank really high so surface of the water is breaking and splashing a lot of water. Im using a glass tops to keep water from splashing outside. I took tops off for a couple hours but water was all over.I really do not want to use tops <i have a nice lights MH and T5s and with glass tops they lose a lot of eficciency>.I know a lot of you guys do not have tops.How you do this? So you really do not have to break that surface? Please explain this to me Thanks for all your help before.

[AMDPhenomX4]

Mainly just have a ripple. Thats all my tank has and its fine. Depending on which fish , More or less ripple. Also you should take the Glass tops off anyways. They reduce the efficiency of the Gas exchange.

[Ruadh]

As AMD says, a ripple is just fine. If you have plants and CO2, putting too much action on the surface will serve to gas off the CO2 faster and you'd be wasting it.
The wave action serves to break the surface tension and allow the water to absorb the O2 from the air.