Floating debris
 

I find my tank is perfect except for floating debris. I only keep one power head one and I don't use RO water . What should I do to fix this problem?

my over flow takes almost all down to the sump whats left I use a small net and scoop it out id there is any I can get at. Since I added an extra power head I have not seen any.
You could try and get an extra power head more flow I found to be good. or use a net and scoop it out.

Bill

Filter socks are an easy solution if you have a sump.

no sump
 

Unfortunately my tank ( red sea max ) is incomparable with sumps so I need a diferent solution

What do you mean by "floating debris"? If you mean the film on the top of your water than you need some surface agitation. A powerhead near the top portion of your tank will help with that and also good to help get gases out of your water.

Possible solutions:
Increase Flow
Get a filter sock
Get open water swimming fish (To eat the detritus)
Get hermits/ detrivours (To eat the detritus)

A sump is going to be your best bet but if that won't work for you then the above should help.
Levi