Lilrodyreefer

i don't have a pipe flow chart, but i usually try to think the bigger the better, to a point. i would think at least 1 1/4" or 1 1/2" sch40 pvc pipe,comming from the pump. trying to use the least amount of elbows witch cause more friction loss. depending on the size of the tank, you might be able to tee off 1 1/2" pipe to give you 2- 3/4" or 1" returns into the tank. i think marc has a great article about working with pvc which might be of help. you can google "pipe friction loss" to give you an idea to help size the pipe, and if the pump is new it should have some info about head pressure and flow loss.

I also had a question here. Is there a correlation between the size of the return piping and the size of the drain. I have an Eheim 1262 pump for a 55 gallon reef and can build up to a 2" drain (that is the size of bulkhead.) My pump, however, leads off with a 3/4" fitting, which I was going to do with 3/4" pipe since it is less expensive than 1". Should I instead do the 1"? Thx in advance.

i would do the 1" just for future expansion. then at the pump reduce

You always want the drain pipe to be able to keep up with the return pump. If the return pump exceeds the drain, the tank can overflow.

Me personally I like my fuge to have a very slow flow, just enough to keep the chaeto tumbling. I drain the tank to a equipment chamber, and then feed the fuge with a small pump from there.

If you were to put 1400gph through your fuge, I would think you would seriously lose the effectiveness of it

I believe Reef Central has a pipe flow estimator. For a sump I'm currently building for a Biocube 14 I decided to use a mag 7. I plan to tee it off back into the refugium and skimmer sections (I'm using a 40 gal. breeder - huge for the DT I know) and control the flow rate with several ball valves. Anyway, I'm using 1/2" flexible PVC on the returns and as few elbows as possible to limit frictional losses. I plan to use a 3/4" drain. At some point along the line I plan to use a SCWD to create an oscillating current of 300gph in the DT. Since this will replace a 240 gph Koralia nano and a 125gph return pump currently in the system I may still end up leaving the Koralia in the tank or even upping the flow. For 400gph flow I would use 2 x 3/4" drain lines to support one oscillating stream flowing through the 1/2" pipes. Maybe all my plans sound like overkill, but I plan to try growing SPS in the DT and I don't think that would be practical in a Biocube 14 any other way. Additionally, I chose the drainlines to be one size larger than the return so that I know the drain will never backup and cause an overflow. The reason I plan on possibly having two drain lines is that It gives me a backup in case a critter gets caught in a drain or some other unforeseen situation arises. That's just my two cents worth though and I'm very new to all this so these are just MY plans. I'm no expert by any stretch.

Use 1" PVC. After you adapt to the pump put a 4" piece of pipe and then a union (glue type), not a coupling....than another 4" piece, than put a glu type ball valve so that you can regulate your flow. all pumps advised for hobby use will be centrifugal type pumps and restricting the discharge has no ill effects on pump. Unoin makes pump easily serviceable.

Right now I have have a 180 interconnected w/ my 26+ yr old 75. the 180 overflows thru a eshopps dual 1" that I connected to 1.25"PVC (two 1.25"). Unions and ball valves on each end w/ tees on bottom w/ female IPS for boiler drain type valves to drain. There is about 20 feet between the two aquariums. Using a mag pump as described in previous post. Oh at the discharge side in the 180 I have the piping come up and over going down into a tee with those spiraling nozzles that spin by water flow. hope this helps