Union PVC on return lines? Handle the pressure? Other options?

I'm setting up a used 120g RR that I picked up and am unsure of how to attach the drain and returns to the bulkhead.


Looks like a standard OEM style bulkhead that's slip - I know it was used before but I can't figure out how the previous owner had it plumbed as there's no PVC glued to it. A quick trip to Lowes and Menards last night and schedule 40 plumbing seems to have different threads (sloppy) if I use a female reducer.


I would prefer to use a female reducer so that I can run 1" to the return bulkhead - with a union I would end up running 3/4". Head loss calculator indicates I'll lose approximately 200 gph going from 1" to 3/4" PVC (965 to 787gph).


Do many of you glue then use a union for the return? I've used them on drains before but am a little unsure if they'll handle the pressure as the return is an Iwaki 55RLT.


Thanks for your input and feel free to ask clarifying questions if I left something out.


-Eric


Picture is showing one return 3/4" and one drain 1"

 

I am sort of following what you are saying. Not sure what SCH40 PVC you found with threads. Are the insides of your bulkheads threaded or slip?

I have unions on both of my returns and drains for my 120 gallon RR and I am using an Iwaki WMD-40RLXT which has 1200 GPH and it is working great. I was at the Cedar Rapids Spring tank Tour and saw a lot less water flow coming out of some of the awesome tanks, but those tanks also had more powerhead water movement than mine.

Your Iwaki looks like it is rated at 1080 GPH, and depending on how much powerhead movement you plan to have, even losing some GPH from the pump through some unions won't hurt too much.


Another option is to get the next size up union. You would need to get the correct reducers to connect the later union to the smaller pipe, but your flow wouldn't be hindered.

Of course, you are still going from 1" down to 3/4" through the return pipe shown in your picture anyway.

Not sure if any of that information helps or not. Sorry if it doesn't.

 

That helps - thanks!


-Eric

 

Fyi those were new bulkheads so dont wonder how it didnt leak lol. Unions hold the pressure just fine. I have a union ball valve a foot off my pump pushing 4000gph and its nothing. Good to see you finally setting this bad boy up! If you need any help jus give me a shout after all your basically down the road.

 

Thanks for the info Casey!

I need to modify the sump (drop skimmer chamber to 7") and put a bulkhead in the sump for the return and it'll be time to move the tank.

I will need someone to help me move the tank from the basement to the 1st floor in the next couple of days - was going to post for help offering frags for help. Have my 72g sold and I promised it by the 22nd.

-Eric

 

David we didnt those were new bheads and we never got around to plumbing it.

 

The previous owner had cut the plumbing right at the bhead so we couldnt use a coupler and go with it. Wasnt much of a favor lol.