View Full Version : Help with plumping 300dd to new basement sump

09/14/2015, 08:43 AM
I currently have 300dd running herbie 2-1" full siphon and 2-1" emergency in each over flow and returns coming over back of tank. Sump is under the tank currently but planning out basement sump room. Just ordered new reeflo gold hammerhead hybrid.

My question is should I run 4-1" flex pvc for drains and 1.5" flex return for tank to basement. Or run 2-1" for full siphon and 1.5" combine the 2 emergency lines into. I'm open to other options, before I order all the flex piping.

09/14/2015, 04:54 PM
Anyone help with this, looking to order flex pvc asap.

09/15/2015, 08:25 AM
i run my 250dd with two return lines (each 1.5" so nothing gets stuck in them after the 1" overflow bulkhead). I do a herbie style setup where one drain in each overflow is tied together just under the tank and run at full siphon and the other drain in each overflow is tied together just under the tank and run as the emergency. I put my gate valve at the end of the full siphon drain line, at the sump in the basement. You might top your full siphon drain pipes with an extra pvc coupling so that you can slide them up or down a 1/4 inch to help balance flow between the two overflows so that both stay in full siphon. I also put a durso style top on the emergency drains to quite them. It might take a few days to figure that out as biofilms grow etc. But, you won't have any noise once everything is set.

Also, I recommend modding the weir. I cut out every other post and used a dremel to make the remaining posts thinner because you don't get a lot of flow through them.

Finally, expect flow to change in a few months as lots of sponges and tubeworms grow - they tend to clog up the weirs that are halfway down the overflows. (I think I wish I'd blocked those entirely at the beginning).

I run my return over the top of the tank.