River Tank Help

[capeldrae]

A couple of weeks ago I posted a question about otto's in river tank, there was a mixed response, so to decide for myself to try for a weak with flo and a weak without. I switched off my powerheads (2x820's).
I switched them on today and there was no power to the flo. I cleaned the filters then cleaned the powerhead at the back and tested it and it was pushing the water out so I connected it to the pipework and there was flo ,there was even suction to the pipe where the front powerhead should be connected. I cleaned the front powerhead and switched it on and there was the usual flo, but as soon as I connected it to the pipe it lost all flo.
The two puwerheads, green and yellow, adjusters are in the same position and both work when disconnected.
I hope someone can help.

[brett_fishman]

try turning the powerheads on without the sponges on the manifold

[capeldrae]

Will try, tomorrow, but they worked with the sponges before.
Thanks Brett.

[brett_fishman]

im thinking a layer of algae grew on the surface of the sponges while the powerheads were off or something along those lines, but you should flush the manifold and try it without sponges to see if its a problem with the powerheads or a problem with the manifold