Max flow rate thru a 1.5" drain is...??

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runway1

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I'm setting up my 120 soon and would like about 1800 gph flow. Considering "reef ready" tanks come with a 1.5" drain hole in the bottom, how much flow can this size hole deliver?

Seems to me that if I get a pump capable of returning 1800 gph, what good is it if my 1.5" incoming flow can't feed the pump?
 
Can anybody anser this for me?? Can I get a 1.5" drain to feed 1800-2000 gph?
 
I have a Oceanic stock 120 RR tank. I'm running a mag12 with an 18 impeller, which from what I'm to understand brings my pump output to somewhere around 1500. That's probably netting close to 1200gph after head loss from height and elbows/Ts. I have a tunze in tank for additional flow.

I'm in the North East and need a chiller due to the mag12 in the sump. I'd go with an external next time.

Also you could use a pressure rated pump and eductors/penductors (I think MyReefCreations makes penductors?) to increase the flow without increasing the throughput. A strange concept, but I've seen it in action and it is amazing.
 
Phyl said:
Also you could use a pressure rated pump and eductors/penductors (I think MyReefCreations makes penductors?) to increase the flow without increasing the throughput. A strange concept, but I've seen it in action and it is amazing.

Do know were I could look for information on eductors/peductors?
The consept sounds very intresting. :p TIA
 
You could use the return hole as a second drain or set up a closed loop with a second pump. I heard Anthony Calfo comment once that the so called reef ready tanks are kind of a misnomer. The flow that really is needed would require a lot more holes ;)
 
The flow that really is needed would require a lot more holes

That's if you wanted all of your tank flow through your sump. That isn't good for your skimmer as the water would be moving too fast to get a good skim on it. Better to have some sort of closed loop/in tank PH for additional flow.

Do know were I could look for information on eductors/peductors?
http://filterpump.com/pdfs/products/112.pdf
http://themantledmonster.thereeftank.com/ediy.html
http://www.kthsales.com/website/Misc/hello_salt_water_enthusiasts.htm

Hope some of those help!
 
I would love more flow than what my reef ready tank can support. I don't think 1800 would be too much. I hope mine is running 700-800 :(
 
Phyllis.. so they make something like a jet of water inside the line using the water preasure in the line..creating more flow?
 
Yes. It creates a jet of water flow coming out of the penductor, though honestly I don't understand the mechanics of it. I have seen it in action though! It will work with a flow pump but not as well as with a pressure pump, from what I've read. This means that the mag pumps are not as good pump to use as say an Iwaki.
 
From the looks of the links you provided it would appear that more water would be sucked into the line. :?:

btw.. this really isnt all that important if the answer isnt known.. its just intresting to me.. :p
 
That's great feedback all, thank you! I'll research this eductors/penductors concept as well.

So far, seems like a seperate, closed loop might be better. Especially considering the issue of flow through the PS - good point. It just means another hole!
 
So, from what I see these eductors/penductors are simply increasing back pressure by narrowing the orifice. This will increase the back pressure and therefore the output pressure.

With this higher output pressure, and therefore output velocity, the conclusion is made that you receive more "flow". Well, not really. What you're getting is more turbulence, more water movement, but not more flow (volume). Actually, you're decreasing the volume by narrowing the output end and raising the back pressure.

In the end, you might achieve a benefit, I guess, by increasing the velocity/turbulence of the water but that's not what I'm looking for in a new tank set up, although very interesting. I'm a Mechancial Engr. by profession. Although I'm a structures guy, I know a bit about flow mechanics..
 
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