Reef Central Online Community

Home Forum Here you can view your subscribed threads, work with private messages and edit your profile and preferences View New Posts View Today's Posts

Find other members Frequently Asked Questions Search Reefkeeping ...an online magazine for marine aquarists Support our sponsors and mention Reef Central

Go Back   Reef Central Online Community > General Interest Forums > Do It Yourself
Register Blogs FAQ Calendar Mark Forums Read

Notices

Reply
Thread Tools
Old 04/07/2010, 10:53 AM   #1
mbrady
Registered Member
 
Join Date: Nov 2007
Posts: 54
Air /water mix standpipe drain system

I currently have a AGA megaflow standpipe in my reef ready aquarium.
I assume this is a air / water mix standpipe drain system. I read some where that it is really a Durso standpipe design (give credit were credit is due).

Can this drain system be split into two feeds into my sump with some type of control value conected to it?


mbrady is offline   Reply With Quote
Old 04/07/2010, 11:06 AM   #2
jacksonpt
Registered Member
 
jacksonpt's Avatar
 
Join Date: Aug 2001
Location: Vestal, NY
Posts: 2,988
Probably could, just depends on how much room you have in the stand. Why would you want to?


__________________
Jackson
- All advice I give is based on my first hand experience. YMMV.

Current Tank Info: 38g, mostly LPS with a 15g sump/fuge plus all the other standard goodies
jacksonpt is offline   Reply With Quote
Old 04/07/2010, 11:19 AM   #3
uncleof6
Registered Member
 
uncleof6's Avatar
 
Join Date: Jul 2004
Location: San Diego. CA
Posts: 9,768
It is nothing but a high priced "durso" modified standpipe. You can make your own for a bunch less, and yes it is an air/water mix standpipe system-- subject to the same flow restrictions (for trouble free operation) as one that is made from easily obtained pvc fittings.

Air/water mix systems are very touchy with restrictions in the lines, and geometry of the drain line. Angles, turns, 90's, valves etc., all cause turbulence in the lines, causing the air and water to mix, rather than remain separated. It is less problematic to feed other equipment or areas in the sump from the return line, rather than the drain line, and keep the drain line as straight and unrestricted as possible. I.E. no valves, no 90's, splits what have you. Valves are used in siphon drain lines, to set the water level in the over flow.

Jim


__________________
I am a PRO, do not try this at home.

On Sales and Marketing: If it sounds too good to be true, trust and believe-- it ain't.

Current Tank Info: 240 5' wide Reef (back in operation)
uncleof6 is offline   Reply With Quote
Old 04/07/2010, 03:19 PM   #4
mbrady
Registered Member
 
Join Date: Nov 2007
Posts: 54
Uncleof6---Follow up question

Drain pipe flow Rate

What is the megaflow standpipe flow rate?

I am currently running an external pump (Iwaki Model #30RXT) which is rated at 900 gallons per hour with an 8 foot head. It runs straight out with no flow control value.

I beleive my return pump is to strong. What do you think.

90 gallon Tank.


mbrady is offline   Reply With Quote
Old 04/07/2010, 05:08 PM   #5
uncleof6
Registered Member
 
uncleof6's Avatar
 
Join Date: Jul 2004
Location: San Diego. CA
Posts: 9,768
The flow rate it will handle without problems depends on numerous variables, however 1.5" standpipes (air/water mix) show symptoms as low as ~ 320 gph-- it can vary. Problems always include noise, bubbles in the sump, and often "toilet flushing." You have not stated any problem, but I would think there is some kind of problem: there should be if you have 900 gph going through an air/water mix drain. You said you believe your pump is too strong, I disagree that it is "too strong" for the system you have. I believe it is "too much" for an air/water mix standpipe. If there is a problem, splitting the drain line will not solve it, but splitting the return line (robbing some flow) will help with the problem-- if there is one. If it is merely should I split the drain line to feed "fuge", it is better not to split an air/water mix drain for reasons above. If it ain't broke-- that just might break it.

Jim


__________________
I am a PRO, do not try this at home.

On Sales and Marketing: If it sounds too good to be true, trust and believe-- it ain't.

Current Tank Info: 240 5' wide Reef (back in operation)
uncleof6 is offline   Reply With Quote
Old 04/07/2010, 05:25 PM   #6
billdogg
Registered Member
 
billdogg's Avatar
 
Join Date: Apr 2008
Location: Grove City, Ohio
Posts: 4,485
Please refer to the attached chart to determine your approximate drain capacity.

As you can clearly see, a 1.5" drain can pretty easily handle AT LEAST 700gph BEFORE siphon effect.

1' drains, on the other hand, which I think is what the megaflow is, begin to have issue at ~300 to 350gph


Attached Files
File Type: docx Aquarium Bulkhead Tests.docx (21.7 KB, 11 views)
__________________
I'll try to be nice if you try to be smarter!
I can't help that I grow older, but you can't make me grow up!
The speed of light is faster than the speed of sound. That, my friends, is why some peop

Current Tank Info: 120 mixed reef with 40b sump, ASM G2 skimmer, AI Sol Blue x 2, and a 150g Soft Coral tank with 120g refugium and 50g sump, no skimmer, VHO T12 lights
billdogg is online now   Reply With Quote
Old 04/07/2010, 06:13 PM   #7
uncleof6
Registered Member
 
uncleof6's Avatar
 
Join Date: Jul 2004
Location: San Diego. CA
Posts: 9,768
billdog, the chart that you posted concerns blank bulkheads, and does not consider interaction with the standpipe. Max flow capacities for bulkheads, or even pipe sizes is relevant to the discussion, but not in the way you are presenting it. The issue is laminar vs turbulent flow. Laminar flow, that will be silent, bubble free, will be far below any max capacity of a given size bulkhead, OR given size stand pipe. The bubbles and noise annoy most people, and the number of threads on the subject far to numerous to ignore. There is a commonality, that can be seen even if the physics are not understood-- or even known. It is always because the flow rate is too high, and/or restrictions in the drain line. A 1" air/water mix standpipe will have problems way below 300 gph, and the inventor of the "durso" states clearly that a 1" durso, is of no real use-- except with extremely low flow rates. My comments have nothing to do with max flow through a bulkhead, through a particular size pipe, or with siphon systems. An air/water mix standpipe flow goes up, thinks about siphon, the "toilet flushes" = flow rate too high. Flow in the standpipe is not laminar (noise, bubbles with or with out "toilet flushing" = flow rate is too high. Laminar flow in a standpipe, is very low relatively speaking. The physics win.

I think before this gets too far, and the OP goes away, give the OP a chance to address the question of what the exact issue is, if there even is one. He stated "i believe my return pump is to strong," that is only telling to a point.

Jim


__________________
I am a PRO, do not try this at home.

On Sales and Marketing: If it sounds too good to be true, trust and believe-- it ain't.

Current Tank Info: 240 5' wide Reef (back in operation)
uncleof6 is offline   Reply With Quote
Old 04/07/2010, 06:56 PM   #8
das75
Registered Member
 
das75's Avatar
 
Join Date: Oct 2002
Location: Edmonton AB
Posts: 2,164
I've split from one on my drains to feed a fuge and controls easy with a ball valve. Can't see splitting though giving more overall flow than a single line would.




__________________
.

Current Tank Info: 145g Starfire display (mixed reef) w/75g basement sump & 20g refugium, Barracuda return, Dart w/OM 4way CL, AI Hydras and Director.
das75 is online now   Reply With Quote
Old 04/08/2010, 09:01 AM   #9
mbrady
Registered Member
 
Join Date: Nov 2007
Posts: 54
OP Response

My megaflow standpipe drains into a Megaflow wet dry now. The water falls through another PVC standpipe into a section in the wet / dry that is 13 1/2"L X 3"W X 17'' high. This section is enclosed except for two inchs from the top one one side. The water than flows over a baffle into a prefilter tray into the sump section. Yes there are air bubbles, occasionally a little toilet flush affect.The bubbles dispate after a short while and do not make it to the return pump. As far as noise the hum from the pumps is louder than the overflow.
If the suggestion was do not split the drain but split the return. I was concerned with limiting the flow back into the main tank. If as suggested the max flow on the drain side is 300 to 600 GPH than a return pump rated at 900 GPH seems to strong. What happens to the 300 GPH difference or does the pump only operate at what the drain pipe flow rate.

MY ultimate goal is to replace the Megaflow wet / dry with a DIY combination sump and refugium.

My concern is presently I can live with the current set up bubbles, occasional toilet flush and little noise.
If I change out the wet / dry with a DIY Sump will I create something I can not live with


mbrady is offline   Reply With Quote
Old 04/08/2010, 12:20 PM   #10
mbrady
Registered Member
 
Join Date: Nov 2007
Posts: 54
Uncleof6---response to flow rate

See my Original post response


mbrady is offline   Reply With Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


All times are GMT -6. The time now is 06:38 PM.


TapaTalk Enabled

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Use of this web site is subject to the terms and conditions described in the user agreement.
Reef CentralTM Reef Central, LLC. Copyright 1999-2014