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SeaHorse_Fanatic
02-23-2006, 07:44 AM
So, I have a drilled 65g. The hole is 2.5" in diameter. I'm assuming that I will need a 2.5" bulkhead for that. Wondering what will the the size of the fittings for that size bulkhead. Do I lose .5" & so I need to get 2" fitting & piping?

Also, what flowrate can I expect from this size bulkhead? It'll probably be pumping up 5' so would a Quiet1 4000 be adequate.

BTW, this is my first drilled tank. Finally switching from KISS to the "norm" now.

Thanks,

Anthony

Veng68
02-23-2006, 08:09 AM
Found this on a site:

Hole Size Bulkhead Size
1.5" 3/4"
1.75" 1"
2.5" 1.5"
3" 2"

not sure of the flow rates.

Cheers,
Vic [veng68]

Static
02-23-2006, 08:24 AM
Like all plumbing parts, the listed sizes for bulkheads relate to the inside diameter of the pipe that can thread into it.

http://www.marinedepot.com/aquarium_plumbing_parts_fittings_bulkheads_straine rs.asp

if you use that chart, your closest size would be a 1 1/2" bulkhead. Hopefully your holes are 2 5/8" rather than 2 1/2".


http://www.reefcentral.com/calc/drain.php

if you use that calculator, it will tell you that 1300 gph is the maximum you'd want to flow through a 1 1/2" drain.

TheReefGeek
02-23-2006, 03:43 PM
A 2.5" hole will fit a 1.5" bulkhead, this is what I use.

What flow rate info are you looking for? Draining capability? Or pumping capability, because these two figures vary greatly.

For drain lines I would double up on the drain lines, but only pump what 1 can handle, so you have built in fail-safe.

I wouldn't push more than 800gph through a 2x 1.5" bulkhead, assuming you are using a durson standpipe or similar. Yes it is possible to do more, but why push it? Get most of your flow from a closed loop, and just flow enough water for 10x - 15x turnover in your sump, otherwise you might run into microbubble trouble.

On the pumping side, 1.5" can handle a lot of flow, I know my barracuda with a 1.5" outlet is 4500gph with no head pressure.

danny zubot
02-23-2006, 05:22 PM
On my 65 gallon I have a 2.5" hole fitted with a 1.5" bulkhead. My return is a Mag 9.5 (950gph@ 0' head) that pumps about 650-700gph at 5'. The bulkhead hole is 75% full with that flow.

SeaHorse_Fanatic
02-23-2006, 06:05 PM
Great. Thanks for the info guys. With the Q1 4000, I should get roughly the equivalent of Danny's setup. Danny, how noisy is that level of flow (75%)? Gurgling toilet sound (hopefully not)?

Any other plumbing experts with ideas/opinions?

TheReefGeek
02-23-2006, 06:49 PM
With my durso standpipes I dont get any girgling noises at all, if you do get some, a piece of airline tubing can usually solve it for you.

danny zubot
02-23-2006, 06:56 PM
with this style I get some gurgle. I need to develope a durso for it.
http://i50.photobucket.com/albums/f343/3214dannyzubot/Reef%20pics/IMGP0072.jpg