sump diagram help

UnseenTric · 05-21-2002, 10:06 AM

My tank specs:
72 gallon bow (drilled for 1" bulkhead), custom sea-life T-3 (850 gph), euroreef CS6-1, 20 gallon long sump (drilled) , 3/4" sea swirl...

I am in the process of installing my baffles for my 20g sump. I am making my own (using some plexi from work). I have attached an image on placement and I height and was looking for a little input.

Couple of Qs
1. If the height of the sump is 12", would a 6.5" baffle be too low?
2. When the skimmer is sitting in the sump it leaves me 19" to the return pump bulkhead. is this enough room for a refugium?or will there be too much water movement here?
3. how much space would you leave between the return bulkhead and the final baffle? Does it matter?

Well thanks for your imput, BTW in the image water is draining from the tank to the sump on the right side...

Doug1 · 05-21-2002, 10:16 AM

In the 20L I used as sump on my old tank the baffles were about 8" hi, and the return side chamber was about 6" wide to allow room for float valve for auto top off. At the return rate you should have with that pump water is going to move thru at a pretty good clip, IMO refuges need slower flowrates to increase dwelltime, Enjoy

karsco · 05-21-2002, 11:18 AM

Hey Tric,
Looks good so far I would raise your baffle heigth if it all possible. I think in my sump it is at about 10" high. To slow down your flow rates you may consider doing what I did. I put the first baffle in at 10" high and let it flow over the top into the refugium. I also put the second baffle in at 10" to create my refugium space. I then cut a piece of acrylic that fit snugly on the top of these two baffles and drilled a few holes in it. That way a majority of the water goes over the top of the refugium and it slows down the flow rate in the refugium. (Kind of like the old wet dry, bio ball systems) It then flows into your third chamber where your skimmer is and then the water is returned to the main tank. The only negative aspect of doing it this way is that you have to clean the top peice of acrylic about once a week due to algae growth from your refugium light shining down directly over it. I hope this made some sort of sense??

R1Bill · 05-21-2002, 11:54 AM

hi tric,

looks good. just make sure to calculate how much water your sump needs to hold under worst case conditions when your pumps go out. then, if you really need to make a refuguim out of your sump, make the baffles as deep as possible to reduce flow. i would probably put in about 5" of sand for your refuge. and, since you don't see the thing, who cares about algea growth unless it gets so long that you need to prune it.

good luck,

bill

UnseenTric · 05-21-2002, 11:55 AM

Doug--
Thanks for clearing up those questions for me.

Karsco-
I like your idea a lot, very clever! One question though, where did you put the holes ... on the top-side, or side facing the return bulkhead?
Thanks again
Pete

karsco · 05-21-2002, 12:10 PM

Tric, I drilled 4 holes each being about 3/16" diamater into the 1st baffle. Since the top piece of acrylic is just wedged in between the two baffles you also get a little bit of water flow on the sides of the acrylic where it meets the glass tank's wall. Hope this helps, and good luck...

Doug1 · 05-21-2002, 10:42 PM

Redirecting the flow somewhat may help but the bottom line is that if you put x amount of water into a given size container and pump out same, the velocity thru it for all practical purposes will be greater in a small sump than it will a larger one, or, at least appear more rapid and turbulent
Is that making sense?
Its kinda like the river anolgy, you have X amount of flow, in the deeper parts of the stream bed(Bigger sump) the water flows slower, but as the river bed gets smaller and shallower(rapids) the velocity increases to maintain the given volume transfer

karsco · 05-21-2002, 10:49 PM

I see what you are saying Doug, but the majority of the water flow is directed over the top piece of acrylic. So this signifigantly cuts down the flow through your refugium. The best thing would to have a seperate refugium above the main tanks water line where you could control the water flow and return the water from the refugium through gravity. But us reefers with limited space have to make due with what we have.