Sump/refug math..

I'm looking to either buy or create my own sump..but I have some questions beforehand..

I'm a newbie at this, so I'm sorry for all the questions! I just haven't found the answers while I've been researching.

Question one:

I know you build each compartment to work around what size equipment you want, for example, you might prefer a larger refug and a smaller return etc etc. But does it really matter how big you make each compartment? Are their rules to it? Or a certain equation to go with it?

Question two:

As far as running the plumbing (Overflow down into sump, along with tubing leading from return to tank) I will be using pvc, along with the correct valves at desired locations. I may be using 45 degree and 90 degree elbows and the like to help the pvc run the right angles in and out of the stand, but I'm guessing with each added turn or elbow, it changes something to do with the flow..also, how long can the pvc be, or does it even matter? I am completely lost on this idea, I'm sure it involves much more math than I'm willing to think about haha. Any help on this?

Thanks so much in advance!!!

 

i thought id be using alot of my pvc and what not... but avutally i found out the only thing i wanted to use pvc on was my return from my pump... and from the over flow to the wet/dry i just used a flex hose...
and from the pump i put a ball valve straight off of it (to regulate flow) then i used a 90, then a T, then 90ed up on both sides and used 3 more 90s, going into the tank... the only thing is... is u need to make sure to put a check valve in some where just incase the power goes out... cuz then the sump creates a back syphen and that could cause water to go EVERYWHERE! lol
HOPE MY PIC HELPS!
DAVID

 

1. Unfortunately, there is no "set" design when it comes to a sump or refugium. B/c all systems are different, what works for me may not work for you. Most, if not all designs are copied from Joe Smo to a trusted LFS. I copied my trusted LFS design with a hint of my custom needs. I did want my refug compartment as big as possible b/c I do have a large bio-load, both in fish and corals. The "perfect" design takes time and exp.
Good luck with yours.


2. Every 45 or 90 elbow represents 1' of head pressure. The trick is to "produce" an uninterrupted flow. So lets say that you have 7' of pvc pipe and (2) 45's and (4) 90's, thats a total of 13' of head pressure. As far as how long can it be, as far as your return pump can handle.

I hope I was able to answer your Q's correctly.



Luna

 

David, this does help quite a lot! I may consider using flex hose now on my drain line. But my question would be this, do you need any valves on your drain?

 

Thanks so much Luna for helping with the feet of pressure deal, that was another thing that confused me. But as far as compartment size, I can basically make it any size I want to? There aren't really any "set rules" when it comes to compartments?

Thanks so much!

 

no not really cuz how ever much water ur pump puts in... it more water ur over flow box will bring right back down... now u need to play with it to make sure ur over flow box is big enough to keep up with ur pump...if ur pumps to fast for it just simply close the ball valve on the discharge of the pump and watch ur water levels very closely... make sure they keep up with eachother and 1 doesnt over power the other... then stuff starts over flowing and u dont want that lol

 

45* angles will cause way less head loss than 90*'s will. If you have to use 90* bends try to find the ones marked "street" as they have a smoother transition and will allow for more flow. In your diagram, if you placed your T at the top of the tank instead of a foot or so down you would have 2 less vertical 90's holding back your return flow. also try to get the T as close to the middle of the tank as possible.

~Will.

 

Elbows and fittings do cause head loss. I hate to refer you to other forums but Reef Central has a very good caclulator on their home page along the left hand side.
Never install a check valve! Check valves fail and cause floods. Thye have no place being in a return line. If you are afraid of flooed you need to provide an air gap where your returns are. This is accomplished by keeping the returns just slightly below the surface so when power goes off a very small easily calculated amount ofwater flows back and xposes the end of the pipe causing an air break or air gap. Same with drilled holes some wil suggest they require maintanance and will fail, too many horror stories when a simple air gap works fine and costs nothing.

 

As far as compartment sizes it's up to you but I would say make them as big as possible(as with your sump,as big as you can go).You get more water volume but also if you ever want to add equipment you will have the room for it. Also I like to make my return section as big as I can so I can go longer without having to top off.If your return section is small (did this with my first sump) you will be adding water more often because of evaporation,unless you do an ATO.

 

Thanks for all the help everyone! All my questions and doubts have been clarified
But I do have a couple more, if anyone can help me.

1. Does the overflow box need to have a higher/lower/equal GPH in comparison to the return pump?

2. Does the return pump and the skimmer pump have to have the same gph?

Thanks!