Help ! Sump problems with flow

saltwaterexotic

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my sump doesn't seem right I tested to with a water hose on skimmer side left in sock and when it gets to refug and than hits return wall with slits 3/8" wide the flow over seems slow a return pump will suck all the water out before it can fill. if I open hose all way my middle baffle water level just flows over it

what can I do ?

sump is 16" tall

my middle baffle is 1" off floor and comes up 12" tall
my outside baffles are 9"
all spaced 1" apart
my return baffle is 11 1/2" tall right at bottom of cuts
 

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Hard to see with the pics sideways & upside down, but my best guess is the slits slow the water down too much.
Either lower the last chamber with the slits or cut some holes lower to allow more flow.
 
changes

changes

I did a slit on last baffle also lower down and that did the trick brought everything lower and flow was better than going through those teeth. No the teeth serve as a back up if slit gets clog ( that's going to be rear chance lol)
 

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Let me see if I have this right:

Water enters the sump on the left, goes over a 9" baffle, under a 12" baffle, then over a 9" baffle, then over an 11 1/2" baffle? Hmmmmmmmmm sumps don't work that way, and it is no small wonder you are scratching your head. Max water level in the sump is set by the first baffle the water goes over. In other words the max depth in any section must be 9" actually, for the water to flow right, only the first section can be 9" deep. The second section would be ~ 8" deep, and the return section ~ 7" deep. The sump should only be ~ 1/2 full in normal operation, so you have way too high a water level.

Sounds to me like the sump is designed to flow in this manner:

skimmer section -> return section <- fuge section.

Put the return pump in the middle, and power feed the fuge on the end with a branch off the return line, and I think your problem will be solved. Do not feed it from a drain line. There is no way it will work the way you are trying to run it, without cutting the thing up...and you followed some bad advice putting the slit in it. Too bad I did not look at this sooner.

This is the way that design is supposed to work:

sump3-7.jpg
 
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thanks for the info I went off my pro flex design sump I had .What do you suggest I do at this point some options with current set up ? last section right side is 22x5x12"tall
 
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I can cover slit and make refug on left but is 22x5x12 enough ? or I can branch off return in refug to break water surface

5.71 gall on side as to stands now I can maybe move baffle 2" and get 8 gallons on refug side
any thoughts ?

it's only a 26"x22" sump
 
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Return section should be large enough to hold sufficient volume, above the pump volute, to allow the pump to run without running dry, due to evaporative loss, for several days—whether or not you use an ATO. The average evap is ~ 2 gallons per day, so the math is very simple. The evap loss can vary depending on ambient conditions. This passive failsafe is far more important than fuge volume, so do not sacrifice return section volume for the sake of a larger "fuge" section. Most in-sump fuges are just nutrient sinks (due to what is in them, and how they are set up and run,) and not all that effective to begin with, so the sacrifice is not worthwhile.
 
I thought a refug should be no less than 7 gallons from what I read ? so you think I should leave refug at 5.71 g as it is would be best and keep larger return area in middle I was thinking of moving baffle 2" over nd both the refug and return would be same size giving me 8 gal refug ?
 
Well there is not a gallon size associated with the fuge, 10% of the system volume is "considered" the smallest practical size, any smaller being a waste of time. However, the return section is more important as the 'fuge' section is optional, the pump is not.

Since the return section will have the lowest water level in the sump, it is not easy to get the passive failsafe of a few days run time, before the pump starts sucking air. Couple that, with the fact that the sump needs to be able to hold all the power out drain down, and the fuge becomes even less important.

Nothing wrong with 8 gallons per, as long as you have the ~6 gallons over the pump (from the point the pump starts sucking air.) Kinda says something about using 10 gallon tanks for sumps....since sumps should only run ~ half full. At the same time, putting the return section in the middle allows you to increase the fuge volume without crowding the pump because with a 16" tall tank, you can increase the height of the fuge baffle to around 13" (don't use teeth, it will be quieter,) without cutting into your power out drain down capacity. That also means that there is a minimum practical size for a three section sump...somewhere in the range of a 30 - 40 breeder; a tank that won't fit under, is not really the greatest to use for a marine system. Picos and nanos present a different set of challanges.
 
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