Return Question

[mrukus]

I am in the plumbing stages of my build now, specifically the return. I am running a Triton 4 pump which I'm guessing has around 750 GPH at the actual head height I have. I am drilling the return and will have a 1" bulkhead to work with and I want to put in a loc line. At that flow rate should I tee it off and have two lines or just the one. And should I use flare nozzles or round nozzles? I want as much of that 1050 flow to reach the DT. I have plenty of capacity in the overflow.

I'm also going to drill the hole as close to the top as possible. I wasn't sure how much of the glass sits in the trim. Is it safe to just go 2 inches from the trim (1.75" hole) or could i get away with 1.5" from the trim (I need to leave room for the bulkhead)

 

[mcarroll]

2-4x the display's volume is more than enough flow to run your sump and the gear in it. I.e. 40 gallon display only needs between 80 and 160 gph.

As far as flow in the tank, your return from the sump will be (or should be, even at 1000 gph) practically insignificant.

FWIW, locline is going to be pretty restrictive to your return if you're using 1" plumbing. I'd consider making a spray bar from 1" PVC.

$0.02

 

[mrukus]

I always forget to mention what size my tank is and what it is. Its a 75 gal and will be a FOWLR to start with slowly adding corals probably around the 6 month mark. not for any particular reason just because.

What is this spray bar you speak of?

 

[mcarroll]

If you do a search on this site, or with a general search engine you'll find lots of examples - even commercially made ones. Essentially, just a PVC pipe, capped at one end, drilled with a series of exit holes. Submerged in some fashion, of course. Mine are generally vertical and hide in a corner, but there's no one right way.

 

[mrukus]

when can I start to edit my posts?

Just looked up spray bar, I think it would look alot cleaner than the locline but wouldn't all those tiny holes restrict the flow even more? To keep it out of the way I would probably have to use 2 90 degree elbows and run it for about 18 inches on the side of the my tank. It would be cheaper though.

 

[mcarroll]

(And 150-300 gph would be sufficient sump flow for that tank.)

 

[mcarroll]

when can I start to edit my posts?

Just looked up spray bar, I think it would look alot cleaner than the locline but wouldn't all those tiny holes restrict the flow even more? To keep it out of the way I would probably have to use 2 90 degree elbows and run it for about 18 inches on the side of the my tank. It would be cheaper though.

There's no limit on the size or number of holes. I did a little math to attemp to have the correct size/amount for my flow, but without being too big, or too small. Holes around 1/4" seem to be a practical size.

 

[mrukus]

Aaaahhhh I see. What size holes would you recommend? Would 1/8" holes spaced 1" apart be enough?

 

[mcarroll]

Aaaahhhh I see. What size holes would you recommend? Would 1/8" holes spaced 1" apart be enough?

IANAMathematician so I don't know what the correct way to figure this is.

Just so I'd have some basis, I assumed friction/head loss, which I didn't want to add, was directly (1:1) related to circumference. (Water rubbing on pipe.) Based on that, I just tried to have at least as much total circumference in exit holes (more the better, really) as in the circumference of the spray bar itself.

Do the math yourself and see what you think, but I think you'll want to stick around 1/4" holes for that reason. By that math, 1/8" would require A LOT of holes and cause other worries for me like clogging. OTOH, give yourself some freedom to experiment too!

Also, I worried that holes bigger than 1/4" would allow unnecessarily free flow of snails and other unwanted traffic to/from the pump. Can't recall for sure if I used 1/4" for mine or something a touch smaller, but it's close.

 

[mrukus]

Drilling was a success. I am plumbing the spray bar now. I was thinking of doing 2 90gs and having it go the width of the tank. upon thinking more, can I use a 90 and a 45 and have it run along the length of the back almost to the overflow? This would be spraying the water towards the front of the tank. It would look alot cleaner painted black like the background.

 

[mcarroll]

Drilling was a success. I am plumbing the spray bar now. I was thinking of doing 2 90gs and having it go the width of the tank. upon thinking more, can I use a 90 and a 45 and have it run along the length of the back almost to the overflow? This would be spraying the water towards the front of the tank. It would look alot cleaner painted black like the background.

If you let coraline grow over the back glass (dunno if you do) the plumbing color won't matter for long. I did use some PVC cleaner to get the black printing off the pipe though.

Oh! Don't glue any of the parts inside the tank. Dry-fit only.

 

[mrukus]

done. Dry fitting was alot easier than gluing it all. Mind if I ask why though?

I also don't know how ambitious this is but I plan on trying to keep a clear back and no coraline on the glass, overflow l or plumbing.

 

[mcarroll]

done. Dry fitting was alot easier than gluing it all. Mind if I ask why though?

I also don't know how ambitious this is but I plan on trying to keep a clear back and no coraline on the glass, overflow l or plumbing.

Well YMMV of course, but I refrain from gluing whenever possible (pretty much just in-tank plumbing like this) because I like to reuse parts whenever possible. I also know that as soon as I glue everything in place I'll have a brilliant idea for an improvement...or realize what a huge blunder I made due to not considering X. So I don't commit to gluing.

In your case the bonus is that it will be 1000% easier to keep it spotless-clean since you don't have to leave it in the tank while you clean it. You might want to sand down the slip-fit connection to the bulkhead to make the spray bar not-too-difficult to remove - you don't want any reason to torque the bulkhead during repeated removals for cleaning. (Make sense?)

I forget if this was already mentioned or not, but make sure to do a power-off test to see how much water gets drained before the siphon breaks and to make sure your spray bar is stable when exposed. (Full gravity kicks in. ) You may end up wanting to drill an "air-gap" in the plumbing closer to the normal waterline (but definitely still under water)...test it first though. If your sump has plenty of room it may not be a problem.