DYI sump problem Please help

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Turbo V6 Camaro

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DYI sump /overflow problem Please help

today I built my DIY sump /overflow

I have a fountain pump that is adjustable from 300-500 GPH

the problem I have is the over flow will not pull water out of the tank fast enough

The DIY overflow is 2 Tupperware containers with the lock on lids

the one in the tank is shallow about 3 inches deep

on the back of tank its about 6-8 inches

A first I tried a 3/4 inch tube, then i moved up to a 1 inch tube, but the water still trickles out, the pump, pumps in faster then the siphon can handle. even on the 300 GPH setting.

what am a doing wrong? I have it set up so even with power outage it will never loose siphon that works I tested it

I'm just not getting the water flow I need to be getting.......
 
This is a DIY overflow?? Can you post a pic?

Several possibility:

1. Not enough (water) height differential between inner & outer box - you might need to lower your drain in the outer box to create a pressure differential to drive the water across the siphon.

2. Not large enough siphon (or air in siphon) .... A 1" siphon should be able to handle 600 gph at ~1" of water pressure.

3. Too small inner box & not enough room for the water to get into the box. For 600 gph, you need something like 14" of "gaps" in your rakers to get fast enough flow into the box.

I suspect the problem is in your inner box. At 3", that is too shallow to allow for much play in the water level. For reference, I made my inner box 6" and wish I had an extra couple inches to play with. By the time I set up my silent standpipe & fail-safe water levels, I had only 3/4" of play left to adjust for the inner & outer box water pressure differential.

At 750 gph, my 1" siphon requires about 1.5" of "head pressure" which put the inner (tank) water level right at the brim of the tank. <Too close for my comfort.> I ended up using 2 x 1" siphons to get the head pressure down to ~1/2" & a much safer tank water level.
 
One more possibility:

4. Too small a drain from the outer box & water is backing up there. You need a min. of 1" drain line (with no elbows or horizontal runs). 2 x 1" is safer in case there is a blockage during use.
 
This is a DIY overflow?? Can you post a pic?

Several possibility:

1. Not enough (water) height differential between inner & outer box - you might need to lower your drain in the outer box to create a pressure differential to drive the water across the siphon..

I tried this but if the inter tank went dry it would brake the siphon I guess the slotion is deaper internal tank here.

the end of the hose in the out box about 4 inchs bel the pick up in the inter box, but the water level is the same if water stops flows into the inter box the siphon would hold, when i moved it down it would suck inter box dry

2. Not large enough siphon (or air in siphon) .... A 1" siphon should be able to handle 600 gph at ~1" of water pressure..
when you say 1 inch you mean from the bottom of the hose to the top of the tank correct?

does it matter the space from the bottom of the containers to the tube? (i left 1 inch or so)
[/QUOTE]

.
3. Too small inner box & not enough room for the water to get into the box. For 600 gph, you need something like 14" of "gaps" in your rakers to get fast enough flow into the box..
Thanks

I suspect the problem is in your inner box. At 3", that is too shallow to allow for much play in the water level. For reference, I made my inner box 6" and wish I had an extra couple inches to play with. By the time I set up my silent standpipe & fail-safe water levels, I had only 3/4" of play left to adjust for the inner & outer box water pressure differential.

At 750 gph, my 1" siphon requires about 1.5" of "head pressure" which put the inner (tank) water level right at the brim of the tank. <Too close for my comfort.> I ended up using 2 x 1" siphons to get the head pressure down to ~1/2" & a much safer tank water level.
I would like the tank level to stay jsut over the boarder on the out side if possible for some reason it bothers me if it is not lol

One more possibility:

4. Too small a drain from the outer box & water is backing up there. You need a min. of 1" drain line (with no elbows or horizontal runs). 2 x 1" is safer in case there is a blockage during use.

i have a 1-1/4 inch drain and hose, all down hill.

I got my hose at Lowes and it seems the 1 inch line does not want to bend well, does it matter how high the hose is in an "arch" for flow?
 
That 1" of water differential refers to the water level difference between the inner & outer box. That is the driving pressure across the siphon.

The tank water level is controlled by the level of your inner box. If the inner box doesn't have enough area to handle the flow, the level in the inner box will be lower than that of the tank, which will in turn decrease your driving pressure.

I found out the hard way that I do need a deeper inner box. <Since I bent mine out of one sheet of acrylic, I can't change it.> If you cannot increase your driving pressure by dropping the drain in the outer box, you will need a deeper inner box. You can try using both your siphons & see if that will work. <However, using multiple siphons (or a wier design) & having a low driving pressure is risky. You want to have fast flow (ie high driving pressure) in your siphons to clear any air bubbles. Too slow a flow & you will accumulate air during use & break your siphon.>
 
okay thanks so far,

this is what i have done

I made a new intake box, much deeper, i drilled 15 5/8" holes

I tested this, I put the pump on full right into the this box in the sump (since its not running.

all the water went out the holes, no over flow, this tells me this box can handle at least 560gph ( since it less the 2 feet above pump the output is 560 according to the box)

next i found some o ring from my car and sealed up the outer tank bulk head (it was leaking)

i then did the same test on this, and all water flowed out the drain tube with out issues,

next i set up everything in the sump tank I set the out box lower. and primed one 3/4" hose.

i put the pump output into the inside tank.

at 300 gph it would hold fine (as in the water would not come out the holes) at 500 it would over flow out the holes

i primed a second 3/4" hose and it still would not hold 500 gph

if the pump was shut off shipon tubes would drain until they lost suction, i think this is becuase i had the outside overflow so low to try and promote flow

so my issue is most defiantly the siphon.

the drain tube is the in bottom leave about 2 inches do i need to extend this tube higher?

why is my flow rate so low? 2- 3/4" tubes should be able to handle 500 gph easily :confused::confused:


obviously i am missing something here
 
What are you using as a siphon? rigid pipes or flexible? corrugated or smooth wall?

Also, that 3/4" - is that ID or OD?

If you are losing siphon with the pump off, your water level in the outer box is too low. You need to raise that - by extending your standpipe - so there is no loss of siphon. You want your siphons to be sitting in at least an inch of water with a power loss just to be safe. Once you get that set, then you can play with the water level differentials in the 2 boxes.

2 3/4" (ID) siphons should be enough to handle 500 gph if set right. <That is equal to one 1" ID siphon.> That is not the same as 3/4" OD tubing. <You need 4 of those to equal a 1" ID siphon.> If you are using flexible tubing, you need to make sure that there is no pinching of the tube anywhere.

How are you placing your siphons? If one siphon can handle 300 gph, 2 should do 600. It doesn't quite make sense that you can't get it working with 2.
 
okay i put everything in tank and it seemed like it could handle the pump on full blast.

and they didn't loose siphon, (they ar 3/4" internal)

BUT

I can figure out a good way to hang the skimmer and out box on the tank and every thing stay where it needs to be

I may end up drilling the tank (risky and the bit can cost some $$$) or finding a store bought over flow (maybe the ones without tubes?) that's reliable
 
It is a bit tough to hang 2 loose boxes ... that is one reason I went with bending acrylics.

The one solution I saw on the web was to drill the boxes & use a few zip ties to hold the two boxes together, then hang it on the tank. That looks a bit loose on the pic, but the guy says it works. A better way I think is to use a hanger. If you can find a U-shape piece of plastic with ~ 1" gap .... may be a long & narrow candy box or something that you can cut up ... you can use that as a hanger. You can bolt the boxes to the hanger with nylon bolts. You can also bolt the hanger to the tank if you drill a hole ( or 2 ) on the tank side of the hanger, & run a bolt through it so you wedge the hanger tightly onto the tank.

Drilling a tank is always risky, even for a pro. Also, most newer tanks are tempered, and the risk of shattering the glass is even higher.

A good store bought overflow is this:
Reef Aquarium Filtration: Eshopps Overflow Boxes
Quite a few here have this & have good things to say.

I would avoid the continuous siphon overflows (no siphon tube, wier type). Because of the low driving pressure of the design, the siphon is prone to air trapping & losing siphon. There were many problems with that reported on the various forums. If you use a continuous siphon OF, you need to run it with a small PH or venturi pump to continuously evacuate out the air from the siphon. Problem with this is that a lot of the "CPR" style OF + pump kits on Ebay & other sites have pumps that are cheap & prone to break down .... and there have been reports of floods when one of those pumps stop working ....

After doing a lot of reading on the pros & cons of the 2 HOB OF types, I decided on a siphon tube design with a high driving pressure. So far ... touch wood ... no floods ... running for 2+ years. <This is basically the eshopps design ... and people here said they never have siphon breaks.>
 
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