simple sump

[Will C1]

mine has never cloged it is clear and only gets coraline growth in it, however now and again it gets an air buble in it you just tap it out dont remove it from the water though just move it up and down tapping it on the down stroke it clears easy enough.

 

[Anonymous]

Will,
If you get air bubbles in the u-tube, your return pump is not strong enough. You need another mag or a more powerful one.