And here is a picture of my first test unit. If you study it closley you will notice that "F" from before is much higher and the riser tube is just shorter. And I also show the drain to the sump and don't use the inside loop surface skimmer.

this picture is a mag 7 pumping against a 4' head.



Hidden behind the hob part is the in tank drain which is just a straight pvc pipe going down about 2/3 the way into the tank.

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fw leiden since 1979, fo salt since 1979, mixed reef 55g 2002-2009. Strong emphasis on the tank taking care of itself. Balanced with plant life, no water changes, tap water, no filters in FW. Only dosing calcium, alk, mag in marine reef tanks. http://www.aquariumforum.com/f15/my-...ods-26410.html
recent tanks (till 2009) 7 years- 10g FW leiden 7 yrs, 55g mixed reef 7, 2 yrs, 20g FW leiden, 10 g fw leiden , 29g mixed reef, current tank 55g leiden