Sump piping
 

Hey everyone!

I am putting in a 20 gallon sump for my 33 gallon reef tank. I am really not sure what size pipe I should be using for the sump. I have decided on a Danner mag-drive 3 pump as my return from the sump to the tank. Any suggestions on pipe sizes?

Depending on what you are doing for an overflow you should have at least an 1 1/2" drain from tank to sump and a 1" return line.

Really? Wow thats allot larger than I though I would need. It will be drilled, so there won't be any overflow boxes.

No internal overflow? I can't say I have seen that before, are you just going to have the pipe exposed and to the top level of the tank?

I use 1" on my dual durso and return, seems to give me lots of flow on my 180.
Before you buy anything, let me know what you need, I have tons of stuff that I need to get rid of.

3/4" return should be plenty for a tank that size

a 1" drain would be ok unless you plan on keeping large snails which could potentially block it

a mag 350 puts out ~ 200 GPH @ 6 ' head pressure so a 1" drain would have to be almost clogged solid to cause a flood
id drill 2 holes and do a herbie style overflow silent and virtually flood proof
return(s) over the back of tank

+1

All the more reason for taking Grizz's advice and go big, are you going to drill the bottom or the back?

you will need an overflow box of some kind to cut off a syphon if power goes out and when you shut off the return pump to do a water change

you could drill the bulkhead close to the top of the water level but you will need to make sure you have enough room in the sump to drain the display down probably 2 inches minimum leaving the 20 G sump to hold very little water
FWIW my 40 G sump only holds about 17-18 G of water and some sand and rock

You can drill the side and use a 90 as the overflow, but I would suggest at least a small box. Is it drilled already? I can give you lots of PVC, so use your money on a box :)