[ScottoMacD]

I have always gone with the theory of 10 to 15 times turnover when it comes to filtration on any of my tanks.

Some of the bigger ones I have gotten away with 8 times but even with my 220 I had to go minimum 10 times.

Filtration is something IMO that you can never have enough of. That was instilled into me as a boy when I started this hobby 30 years ago.

I also prefer numerous smaller filters to one large one. Just a piece of mind thing.

I still believe in it and I still preach it when I'm asked.

Now in a smaller tank like a 10 or 15 one filter will suffice but it has to be a higher rated filter than any manufacturer recommends. Basically because as previously stated this hobby is now big business (unlike the old days) and BS reigns. Over rate your product and Sell sell sell.

If you get them (the customer) to by a filter that just meets their current needs they will be back to buy another when those needs change.