LeafsFan

I have a Hagen Hush 20 power filter for my 15g tank. It seems to work well, but I find that most of the fish are sticking to the side of the tank furthest away from the filter. I suspect this is due to the output flow that seems to create quite the downward current and some bubbles in the water. I noticed that when any of the fish venture over towards the filter, they get pushed down in the tank by the current and usually swim back to the other side to hang out.

The filter does have an adjustable flow rate (set to max out of the box), but I'm wondering if I reduce the flow rate if it will still provide adequate filtration for the tank. Am I correct in thinking the reduced flow would be caused by a reduction in the strength of the filter input?
The manual identifies the dial to adjust the flow rate, but doesn't offer any suggestions as to when or why you would want to adjust it.

Does the output waterfall also assist in adding oxygen into the water?

Stephen 31

Hi Leafs

The Bubbles that the filter flow creates does help with the oxygen levels in the water. Your water is not too warm so it wouldn't be a huge issue anyway. You will get other opinions I'm sure but I think turning the dial down a little won't have a big impact on the filter quality and i think your fish will appreciate it.

Stephen

aquarist48

Good morning. I agree with Stephen 31. If the flow rate is too strong in your tank, adjust the flow rate. With my Aqua Clear it doesn't slow the intake just the output. Oxygen is created by movement at the top of the water.
You can also go to the top of this page, click on Fish Forum Home. Look under General Discussion, then DIY for ideas on diffusing flow.
How To: Slow Down Current From A Filter

LeafsFan

Thanks for the tips....I reduced the flow rate by about 25% and this seems to have made enough of a difference to keep everyone happy.

aquarist48

Glad to hear it!