| It looks like you have one of those Red Sea Berlin skimmers. IMHO, there is a design error in that the output hosebarbs are too small. Whey I had this skimmer, I removed the original hose barbs and replaced them with PVC 3/4" pipe thread to 1" slip adaptors. Double check the size.
Then I used rigid PVC pipe to construct the returns to the sump. The pipe should be installed so that is is on a slight downgrade to the sump, about 1 inch per foot of pipe. This gives you a down slope and prevents "traps" like you get with plastic tubeing. The water will flow better because air bubbles will not get trapped in the pipe.
It may also be necessary to add a "vent stack". As close to the adaptor as possible, install a T so that it points up and connect a short length of rigid PVC pipe in the T so it reaches the top level of the skimmer. This allows air in and out of the return pipe, and acts similar to a vent stack in a home.
Total cost to do this should run you under $10, for the length of pipe, and the fittings, maybe a little more if you need cement and primer.
BTW, I would consider the skimmer too small for the tank you have, but since it's a school project, you may have to go with what you have. Perhaps you can get some students to build a downdraft skimmer, or something similar in shop? |