Ok... I'm having my live rock filter as suggested to make all things
natural for my tank... BUT I have been told that a live rock filter
system will half the ammount of fish my tank can take...

How many fish will my 40 (UK Gal) tank take with coral and cleaners in
it? It's been hinted that my tank may only take 2 fish...?

Will having two filters (i.e. having a mechanical/bio filter
too)increase the amount of fish?

Thanks for your help....

Dan