Mentzer;751321; said:Thanks for your input. Yes I do have sand as my substrate. When I install my next tank for them in the summer I shall be going bare bottom. The flow rate is still strong but yes I have heard washing/swishing sounds from within the canister. The only conundrum remaining is the fact that the other FX5 at the other end of the tank never misses a beat. I am currently waiting on Hagen UK's response.
I'd be very interested to hear Hagen's response, If you could cut and paste it here it would be much appreciated!
Cheers

