Headache forming from my new DIY sump

[truehle]

I'm stumped. I have a 125gal DT with a newly setup DIY 33gal sump/refugium.
The overflow box is an Eschopps 1200, rated for 1000gph. There are x2 1" lines extending from the overflow box to my sump into a filter sock. I have the pvc extending about 3" below the water line. Each 1" line has x2 90 degree elbows, x1 union coupling, and x1 ball valve. I should be able to get 600 gph each for a total of 1200gph max.
My return pump is a mag-drive 9.5. On the 1" PVC return line, there is 3.5ft of head pressure, x5 90 degree elbows, x2 union couplings, and x1 ball valve. From charts, I expected a maxium of 750gph through the pump when I derate due to head loss.
When I turn on the sump pump, the water very quickly lower in the return section, and within 10-15 seconds will start to pull air. The U-tube is completely filled with water, and water seem to be "generously" pouring into the overflow box. (There isn't suppost to be 2 U-tubes on this particular model is there?) I do get some surge and "burping" in the filter sock, but can that be limiting my flow that much?
Other info...In the sump, baffles are separated by 1", and bubble traps have the center baffle up 1" from the bottom. I'm also using a 200 micron filter sock.
Currently, I'm having to almost close the ball valve on the return line to prevent the levels from dropping. I'm at a loss.... Where do you think my flow is being restricted by that much???

 

[salty blues]

Originally Posted by truehle
http:///forum/post/3022921
I'm stumped. I have a 125gal DT with a newly setup DIY 33gal sump/refugium.
The overflow box is an Eschopps 1200, rated for 1000gph. There are x2 1" lines extending from the overflow box to my sump into a filter sock. I have the pvc extending about 3" below the water line. Each 1" line has x2 ball valve, x1 union coupling, and x1 ball valve. I should be able to get 600 gph each for a total of 1200gph max.
My return pump is a mag-drive 9.5. On the 1" PVC return line, there is 3.5ft of head pressure, x5 90 degree elbows, x2 union couplings, and x1 ball valve. From charts, I expected a maxium of 750gph through the pump when I derate due to head loss.
When I turn on the sump pump, the water very quickly lower in the return section, and within 10-15 seconds will start to pull air. The U-tube is completely filled with water, and water seem to be "generously" pouring into the overflow box. (There isn't suppost to be 2 U-tubes on this particular model is there?) I do get some surge and "burping" in the filter sock, but can that be limiting my flow that much?
Other info...In the sump, baffles are separated by 1", and bubble traps have the center baffle up 1" from the bottom. I'm also using a 200 micron filter sock.
Currently, I'm having to almost close the ball valve on the return line to prevent the levels from dropping. I'm at a loss.... Where do you think my flow is being restricted by that much???
When you first start the pump, how high above the first baffle is the water level?

 

[eric b 125]

you dont need ball valves on the drain lines

 

[salty blues]

Originally Posted by Eric B 125
http:///forum/post/3022941
you dont need ball valves on the drain lines
Yeh, you don't really need them, but they can come in handy when doing sump maintenance, etc. jmo

 

[truehle]

Originally Posted by Eric B 125
http:///forum/post/3022941
you dont need ball valves on the drain lines
I made a mistake when I typed it up. I only have 1 ball valve on each drain line from the overflow box. I thought it would be a useful maintainence feature.

 

[tropills]

how full is your sump when you have all power turned off. it should be nearly full with nothing running. this will be your max. fill when there is a power outage or when doing maintenance. with the sump full start the return pump.

 

[truehle]

Originally Posted by tropills
http:///forum/post/3022955
how full is your sump when you have all power turned off. it should be nearly full with nothing running. this will be your max. fill when there is a power outage or when doing maintenance. with the sump full start the return pump.
The sump is about 1" below completely full when the system is turned off.

 

[truehle]

Originally Posted by salty blues
http:///forum/post/3022928
When you first start the pump, how high above the first baffle is the water level?
Maybe I'm not understanding correctly. The water is just barely cresting above the baffles for flow through the tank.

 

[todj2002]

I am about sure there should be two of the clear u tubes for that model. i would just use some pvc and make another and that should help.

 

[wattsupdoc]

You have too many restrictions on your drains. Drains don't figure like returns do. You should have 0 hard 90s on your drains. Additionally any horizontal runs need to have some fall to them. # inches below the water line can cause surging. Perforate the line or cut it to withing 1/2 of being under the water. If your going to have ball valves then expect even a wide open valve to be a big restriction. You should increase these at least 1 size up if using them on the drains. Also. How is your syphon break installed? It should be right at the water line just barely under it. Make it a tad bigger if it's teeny tiny. The more air it sucks in the more you can add to0 the system as it will drain less below. If you are full to within 1 in when shut down and your not getting enough flow through it then you didn't calculate and design your sump correctly. Additionally you may need the second U tube, I believe that the 1000 gph requires 2. You can make one with pvc if you have some left over.

 

[truehle]

Originally Posted by TODJ2002
http:///forum/post/3022974
I am about sure there should be two of the clear u tubes for that model. i would just use some pvc and make another and that should help.
I will try contacting the company that I bought the Eschopps overflow from. Maybe it was a returned item that wasn't repacked correctly.
I thin I'd agree with there needing to be two u-tubes. It feels like not enough flow is getting to the overflow, even with the in-tank box fully submersed.

 

[todj2002]

i just looked it up and it uses two u tubes.

 

[truehle]

Originally Posted by wattsupdoc
http:///forum/post/3022975
You have too many restrictions on your drains. Drains don't figure like returns do. You should have 0 hard 90s on your drains. Additionally any horizontal runs need to have some fall to them. # inches below the water line can cause surging. Perforate the line or cut it to withing 1/2 of being under the water. If your going to have ball valves then expect even a wide open valve to be a big restriction. You should increase these at least 1 size up if using them on the drains. Also. How is your syphon break installed? It should be right at the water line just barely under it. Make it a tad bigger if it's teeny tiny. The more air it sucks in the more you can add to0 the system as it will drain less below. If you are full to within 1 in when shut down and your not getting enough flow through it then you didn't calculate and design your sump correctly. Additionally you may need the second U tube, I believe that the 1000 gph requires 2. You can make one with pvc if you have some left over.
I have the anti-siphon hole about 1/2" from the surface of the DT. I wasn't happy with 1/8" hole for I increased the size slightly. After sump pump turned off, anti-siphone kicks in just fine. I can fill the additional 1" space with more water without an issue. I think the DT drains about 3 gallons when return sump is shut off.
From what I can tell, having the single ball valve and couple 90's on the drains doesn't seem to be limiting the flow. Seems like the overflow box (outside of tank) is "thirsty" for more water. It definitely drains faster than water can be provided.
Where the valves and joints are causing a lot of restristions on the system, it seems like maybe the single u-tube is the problem. I will try adding a pvc u-tube tomorrow to see if it remedies the situation.

 

[wattsupdoc]

Originally Posted by truehle
http:///forum/post/3022984
I have the anti-siphon hole about 1/2" from the surface of the DT. I wasn't happy with 1/8" hole for I increased the size slightly. After sump pump turned off, anti-siphone kicks in just fine. I can fill the additional 1" space with more water without an issue. I think the DT drains about 3 gallons when return sump is shut off.
From what I can tell, having the single ball valve and couple 90's on the drains doesn't seem to be limiting the flow. Seems like the overflow box (outside of tank) is "thirsty" for more water. It definitely drains faster than water can be provided.
Where the valves and joints are causing a lot of restristions on the system, it seems like maybe the single u-tube is the problem. I will try adding a pvc u-tube tomorrow to see if it remedies the situation.

I give up...

 

[truehle]

Originally Posted by wattsupdoc
http:///forum/post/3022997

I give up...
Did I complicate it more?

 

[todj2002]

i believe he is refering to ur valves and 90's. put another utube on it and u might be cured. i agree with not needing them on the drain line tho. not needed. turn of return pump, and once the water level in dt goes below eshopp intake then no more flow.....

 

[truehle]

Originally Posted by TODJ2002
http:///forum/post/3023008
i believe he is refering to ur valves and 90's. put another utube on it and u might be cured. i agree with not needing them on the drain line tho. not needed. turn of return pump, and once the water level in dt goes below eshopp intake then no more flow.....
I called the manufacturer, and Eshopps went with a single larger u-tube instead of the two smaller u-tubes. As its the simplest fix, I will try adding an additional u-tube to see if that helps.
If not, then I will rework the plumbing by removing the single ball valve on each 1" drain line, and remove the 90 degree elbows and replace with 45's, and make sure that I have a constant downward slope towards the sump. Or even possibly try to find a flex tube to extend from the overflow box to the sump.
Any other suggestions?

 

[scsinet]

You have a 33g sump... but you mentioned baffles. How big is your return section? To be honest, if you hadn't said 33g, I'd have thought this was a classic mismatched sump to aquarium size. In the operation of an overflow, the tank's water level has to rise to a point somewhere above the overflow for water to spill in. How far above is a function of pump capacity and overflow capacity. Usually it's around 0.25 - 0.75". That doesn't sound like much, but in a 125g standard tank, that's 1.5-4.5 gallons of water. Your sump, at system rest, has to have enough capacity to handle this, plus the water in the plumbing, etc when running. If your return section is too small... it may drain out before it all "gets going."
The other cause may be your siphon breaks.
If they are too small, the siphon doesn't break fast enough. This causes the water to drain down further than it should at power loss. Therefore, you are leaving room for that extra drop in your sump and lack enough room for sufficient operating water.

 

[truehle]

Originally Posted by SCSInet
http:///forum/post/3023446
You have a 33g sump... but you mentioned baffles. How big is your return section? To be honest, if you hadn't said 33g, I'd have thought this was a classic mismatched sump to aquarium size. In the operation of an overflow, the tank's water level has to rise to a point somewhere above the overflow for water to spill in. How far above is a function of pump capacity and overflow capacity. Usually it's around 0.25 - 0.75". That doesn't sound like much, but in a 125g standard tank, that's 1.5-4.5 gallons of water. Your sump, at system rest, has to have enough capacity to handle this, plus the water in the plumbing, etc when running. If your return section is too small... it may drain out before it all "gets going."
The other cause may be your siphon breaks.
If they are too small, the siphon doesn't break fast enough. This causes the water to drain down further than it should at power loss. Therefore, you are leaving room for that extra drop in your sump and lack enough room for sufficient operating water.
Let me ask this then, because I'm having a hard time finding information specific to my scenario....
I have my anti-siphon holes drilled about 1/2" below the desired water line in the DT, and the prefilter box to the overflow is adjustable. Should the level at which the prefilter box lets water in be about equal to the anti-siphon hole? In any event, I've tested the backflow for when pumps are off, and I'm quite happy with those results.
I think I understand yout thoughts that my system might be trying to play catch-up, and is unable to reach a state of equilibrium in the case of flow. BUT, I've monkeyed around with the system enough to discover that I can basically remove the prefilter box (have the utube directly in the DT), and the return section still will run dry. That's what I don't get.....I've got a overflow rated for 1000gph max, and a return pump rated for 750gph at 4' head pressure, and the pump is still beating the overflow.

As I watch the overflow, its like it can't get enough water to fill bring enough drain water to the sump. That's why I not so much concerned about the restrictions on the drain line.
Could it be possible that because I upsized to a 1" return line (200psi PVC) from the 3/4" outlet that I'm getting a much higher gph that I anticipated for? Because are the charts created for 3/4" pvc for this particular mag-drive? I just feel like either I'm grossly overrated in my pump selection, or underrated in the overflows. Maybe I should put 3/4" on the return line and be done with it.

 

[wattsupdoc]

Originally Posted by SCSInet
http:///forum/post/3023446
You have a 33g sump... but you mentioned baffles. How big is your return section? To be honest, if you hadn't said 33g, I'd have thought this was a classic mismatched sump to aquarium size. In the operation of an overflow, the tank's water level has to rise to a point somewhere above the overflow for water to spill in. How far above is a function of pump capacity and overflow capacity. Usually it's around 0.25 - 0.75". That doesn't sound like much, but in a 125g standard tank, that's 1.5-4.5 gallons of water. Your sump, at system rest, has to have enough capacity to handle this, plus the water in the plumbing, etc when running. If your return section is too small... it may drain out before it all "gets going."
The other cause may be your siphon breaks.
If they are too small, the siphon doesn't break fast enough. This causes the water to drain down further than it should at power loss. Therefore, you are leaving room for that extra drop in your sump and lack enough room for sufficient operating water.

Hence my statement of calculating the sump design properly.
Your drain lines are surging. This is because they are restricted. The water backs up at the restriction until it increases in volume enough that gravity can pull it down, then it flushes just like your commode does. Unrestrict the drains.
Lowering some baffles in the sump would help. Increasing the return pump compartment would help also. But regardless the restrictions have to be removed. Increasing tom1 1/4 with no restrictions is my recommendation.
What are the actual measurements of the sump and all baffles installed?