water flow thru sump

[bcoffey]

i am designing a custom sump with three compartments is it a good idea to have the return in the middle or should it be in the last compartment.
The way i have it designed now is as follows 1. skimmer 2. return 3. refigum.... any thoughts would be appreciated.

[medicdiver]

Probably need a little more info. Tank size, sump size, compartment sizes. Having the return in the middle is fine, but you will have to split your inflow line to flow to both sides. Reasoning is that you dont want the same water flowing through the refuge and the skimmer, kinda defeats the purpose. If it goes through the skimmer 1st, you lose the food for the refuge. If you go through the refuge first, you lose the pods in the skimmer. IMO, the skimmer side needs to be circulating about twice as much as the refuge side. For this you will need to valve both side inflows. Again a drawing or more info would help......

[Fly Guy]

I kind of disagree with that. Whether or not a refugium actually binds up more nutrients than it releases is debatable. Whether or not it does it fast enough to warrant not skimming the water before returning it to the tank is not IMO. If you dont skim the water after the refugium you will be sending dirty water back to the tank. If you want to move any pods to the tank from the refugium you do that manually and dont rely on the being sucked into the return pump to make it there.

Your return pump(I.E. sump flow), should be roughly sized in accordance to what your skimmer can process. The goal being as little unskimmed water as possible being sent back to the tank.

When i used to use refugiums I would put the 1. refugium, 2. skimmer, 3. return. And the drain line would be split so that the throughput to the refugium was less than the rest of the sump.

jmo

[medicdiver]

And I guess a debate it is . I agree that you should skim as much water as possible. What I was referring to is placing a bigger size overflow, spiltting that line into 2 and controling how much water goes to the refuge. You will still need to keep your skimmer and turnover rate up, but some of the extra water can go freely through the refuge and you wont have to worry about manually placing pods. They will flow at a constant rate, instead of all at once. And yes, they will be sucked through the return pump, sounds harsh but it seems to me to be more stable and constant ( as well as one less thing to do). The little bit of water turnover going through the refuge will not cause any problems in the overall water volume..

(and the table turns back to Fly Guy)

[Fly Guy]

Its all a matter of how efficient you want to set up your water cleaning process. I prefer to set mine up so that a refugium isnt even a necessary thought. But for those that DO want to use a fuge, the water still should be skimmed before going back to the tank IMO.

For fun...put a screen up on your return pump output and see just how many pods actually make it to the tank. They have no reason to leave your dirty, comfy fuge to the dangers of the roaring return pump.

[medicdiver]

Ok, but think of a new (dirty) tank. The bloom that occurs and then you have thousands of pods growing on the glass, rocks, sand, etc. They initially are in the water column until they attach to something. So why would it not work in the same mannor for the fuge. The young would get flushed into the main and set up there. Therefore eliminating the needs to transfer pods. The skimmer would more than likely get 99% of the pods going through it (depending on how good the skimmer is). So IMO it is best if you are going to have a fuge, to make it seperate from the skimmer. Its not the big pods that will make it anyway, but the young ones that will continuously make home in the main display. And yes, I agree that all water should be skimmed. But lets say for example, I have a return pump rated at 600 gph. But I get a pump that is 800 gph. Thats 200 gph that I can run through my fuge and still keep the flow through the skimmer the same as original. I will still be skimming the same amount of water as before, but now I have the benefit of pods being constanly introduced to my main tank. Dont take this as an attack, but this is an issue that I see coming up a lot. And I wanted to voice my opinion on it.

[Fly Guy]

All i can say is to do the experiment I stated. secure a fine mesh screen of some kind over your return pump output(s). Then come back and report if there were enough pods making it through from the fuge to benefit anything in the main tank.

And for me, intentionally setting up a sump that sends back 25% of the water to the tank unskimmed is unacceptable.

[medicdiver]

Ok Fly, We will just have to agree to disagree. Bcoffey, You have two totally seperate opinions, but that is what a forum is for, opinions! Fly, it was fun, and I'll let ya know.. and thanks for the nice comment on my pics thread.

[bcoffey]

thanks for the info guys what you both said makes sense i guess this is going to be a personal decision i will keep researching.

[bcoffey]

one other thing the return pump is a mag 9.5 how many gallons minium shoud the sump hold.

[Fly Guy]

Originally Posted by bcoffey

one other thing the return pump is a mag 9.5 how many gallons minium shoud the sump hold.

How much the sump should hold is not really relevant so much to the size of the return pump unless we are talking a really big return pump, which we are not

Just make sure to put a ball valve on the output of the mag 9.5 so you can taper it back according to how much water your skimmer is actually processing. And make sure that the sump has enough capacity to deal with any backsiphon from the tank when you shut the return pump off.

the bigger the sump the better is always the rule, and you would be doing yourself a favor by hooking up some kind of automatic top off device to account for evaporation. This eliminates the need for yout o dump freshwater in every day to account for this, as well as just keeps your salinity the same throughout the day.