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Old 04-04-2010, 03:34 PM
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StirCrazy StirCrazy is offline
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Ok this whole thing is bing made a lot more complacated that it has to be. let me try clarafy and put an end to the back and forth which is getting no where and just confusing people reading this.

Ok so I will put forth 2 senarios for you to read and tell me which one works better all equipment is the same so tank is 80 gal sump is 30 gal, skimmer is fed by a 500gph pump

so senario 1, lets match the skimmer so the return flow is 500 gal per hour

Senario 2, lets use a bigger return pump so the flow is 1500 gph.

and heck let throw one more in
senario 3 lets match the tank, flow rate is 30 gal per hour.

so in senarios 1+2 the skimmer is given all the water it can handle but yet in senario 3 you are starving the skimmer.

so lets pick a number and say that this skimmer is 20% efficient (picked 20 as it is easier to work with) which means in 1 hour this skimmer will reduce the "crap" in 500gal of water by 20%

so our total water volume in these systems is the same at 100gal

system 1 the skimmer has all the water it can handle so it reduces the waist to it theoretical maximum reduction. as per the article Mr Wilson poster that is about a 80% removal.

in system number 2, the exact same amount of water is processed, so you get the same results as system 1.

but in system 3 where we matched the tank size for a 1X turnover, the skimmer only sees 80gal in that hour, but since it skimms the hell out of that 80 gal it is reduced to the max pull down so 80% clean 20% dirty then mixed with the 100% dirty water in the display so 80 gal at 20% mixed with 20 gal at 100% is going to give you about a 35% dirty mixture as aposed to the 20% from the first 2. so you can see if we matched the sump flow for a 1X turn over it would be even worse as we would have 20 gal of 80% clean water mixing with 80 gal of 100% dirty, which would end up with a number of 84% dirty.

So what do we get from this, not enough flow is very bad, to much flow works good but isn't efficient in power used for moving the water.

heaters will work just as good in high flow as in low flow but they transfer more heat to a perticular sample of water in a lower flow, but in a closed system where we have constant cirulation the end result will be the same. and to low a flow can cause heat gradiants which you don't want. as for UV this is a hard one as you have to match the flow written on the UV unit.. mine wanter 400 to 550 gph so I gave it a 550gph pump and knew there would be between 50 and 100gph of losses, chiller same thing match the flow rating.

so the way I had my tank set up I created massive amounts of flow in the display to keep everythign suspended. my surface was very turbulant so I never developed bio film that needed to be skimmed off the surface. but I still used a smooth overflow to reduce noise and I had the water flowing over it at a depth of about 1/4" so I would have enough water flow to carry suspended junk to the sump.

from the sump I had one pump tt remove water for my skimmer, this sucked from my settling pond and returned at the return pump chamber, my heaters were located in the settleing pond where the flow was a little lower. I had two pumps pull water out of the return pump chamber and send it to the chiller and the UV then return at the very bigining again to help keep the flow in the bigining section very fast and turbulant so any suspended matter wouldn't fall out befor the settling pond.

the result of this system was very very little cleaning of crap from the bottom of the desplay, but lots from the settling pond which is what I wanted. I would shut down the return pump, skimmer pump and UV pump, suck all the water from the settling area (about 20) then put my new salt water in there and water change and clean up was done. I don't like refuge, algae or anything else in the sump, as they do need a low flow, so I had my refuge remote and I pumped water to it and it trickeled back into the display directly.

Steve
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