Two overflow drains or a drain and a return

Hey everyone I am getting ready to do my 120 to 200 swap this weekend and wanted to see what you all are doing with your overflows. Each of my two overflows has two holes. Generally one is used for a drain and the other for the return back to the tank. In talking with my LFS the recommended that I used both (all four holes a drains) and hard line the return with PVC up the back ofnthe tank.. What are your thoughts on this.

Any advantages/disadvantages??

Thanks form the help!

 

That would be pretty darn silly. Absolutely no good reason at all.


However... as for an alternate use of the holes in your tank...two words... Herbie overflow. Learn it, know it, love it. Best mod you can do.

 

I would run at least 3 of them as drains. Do a bean animal setup and put a valve on one drain for a tuned full siphon, let the second drain handle the little bit that the siphon isnt catching, and have the third as an emergency backup with an up-turned elbow. It's not silly at all to run that many drains, especially if they are 1 inch bulkheads. I would rather have redundant drains than water all over my floor.

 

I think his was their and my thought in going with 4 drains. It's an in wall set up so the PVC plumbing up the back of the tank will not be seen. I really do have to read up as I have not plumbed a drilled tank before and just want to make sure I get it right the first time.

 

It would all depend on what your return pump gph will be.

 

There is really no point in doing a Bean with a drilled tank. 3 drains is overkill and Beans design is totally custom using much bigger drains than needed and a Calfo overflow.

Drilled tanks are set to provide plenty of drain for the amount of return need for the tank to send plenty of water to the sump. there is no need for turn over, you are just supplying equipment in the sump.

 

Going to be running a Blueline 70 pump which is about a 1750 gph pump a zero feet. I'll be going up about 5 ft.

 

So would you say do a drain and a return on each side? So two drains and two returns?

 

To make plumbing simple you can tie the two drains together to just one line going to the sump, but you need a big enough line to flow both... so 2 one inch drains going into a 1.5" line... which can flow two drains.... with a Bean they would all have to be separate. With a Herbie you have to tie the drains together to use one common gate valve, but again a 1.5 will do.. use a 2" if you want.

Since it is in wall you probably will not have much noise that you care about, but a Herbie is good for eliminating bubbles in your sump too.... but if you do not want to do any of this... just keep the drains drains... it is plenty of flow.

 

ya... much better for splitting flow... and if you look the two holes should be different sizes. Not always, but most pre drilled tanks use the large for drain and the small for return.... if they are all same size even better reason to doa Herbie.

since the return over the back won't be seen, you still may want to do that anyway... just put one return through a spray bar down the back of the tank, you can split it too, but I put all my return down the back to provide flow behind the rocks and to keep it cleaned out.