external overflow question

[alti]

i recently upgraded my return pump and the external overflow box i have cant keep up with the increased flow. would adding another drain tube to the overflow box increase the gph it can handle?
if this is possible the other problem is that the origional hole for the return line is located almost dead center of the overflow box. i think the acrylic would crack if i drilled another hole so close. would i be able to drill a hole in the side of the overflow and use a 90 degree angled fitting?
thanks

 

[oceanjumper]

Possibly. I once thought about adding a second drain to the external overflow box (see picture).
If nothing else, you could T the return line and pull off some of the flow back into the sump.

 

[melbournefl]

Ocean, what program do you use for your drawings?
Thanks,
Paul

 

[alti]

the picture is exactly what i had planned to do. can you think of any problems that may come up with this setup?

 

[broomer5]

Are you saying that the tank level is rising up faster than the overflow box ITSELF ( inner and outer ) can handle - or just the single drain line ?
Describe what's happening more .. please
The overflow "system" is limited by the diameter of the U tube too.
If you add another drainline to the outer box - this may or may not do it.
You may also need to add another U tube as well - depending on just "how much" over capacity your return pump's pushing up to the tank.
Or add another entire external overflow.
What size you got now - and what return pump ?
How big's the tank ?

 

[oceanjumper]

Paul,
I make the design first in PowerPoint. I *group* all teh individual lines etc., press Ctrl-C, open Adobe Photoshop, make a New file. Press Ctrl-V, save it as a .jpg et voila.....
Alti, I never made/used it. I asked around and likely there wouldn't be any problems. Nevertheless, since Broomer is in the house, follow his advice first.

 

[broomer5]

Hey man !
Don't listen to me LOL !!!
OJ - your set up blows mine outta the water !
I'm getting ideas from watching you guys !!!!
You know what you're doing !

 

[alti]

the tank is a 90 gal and im using a quiet one return pump. the overflow is amiracle which is only rated for 400 gph. i had added another u-tube previously and it did seem to increase the flow. i do have another overflow box that is roughly the same size and was planning on using both of them, but i am just trying to avoid having to take my canopy off to saw a hole in the back for the additional overflow box.
i have never actually turned the pump on full throttle to see whether it will overflow the tank or the box. i just turned the ball valve until the overflow box started to sound like a rushing river and the level in my sump began dropping instead of staying level. the pump is rated over 700 gph at 4' of head, so i was never really expecting to overflow to be able to handle it.

 

[oceanjumper]

Alti,
If I were you I would T my return line (with a ball valve of the split-off). This way you can make maximum use of your overflow capacity. Personally, I no longer trust valves directly attached to pumps. I feel they build up the internal pressure when you close them. Not so long ago this resulted in breaking of the valve and the sump pump squirted water all over the place.
With a T you direct the excess water (and pressure) back to your sump (or you could lead it to a refuge).
Broomer posted a few days ago a picture of his T. Following his design I made my own and it works nicely. Total costs: less than $15.

 

[alti]

thanks for the advice.
i didn't sleep very well the first couple of nights i had it hooked up. i could just imagine the pressure building up and pushing the tube off the pump. i even had a dream of trying to explain to my landlord (lives downstairs) why there was 10 gallons of saltwater leaking through his ceiling.
the ball valve is only temporary. one way or another i am going to take care of this problem by the end of the week. if i cant modify this overflow i am just going to have to get off my lazt butt and dismantle my canopy and cut the hole for the additional overflow box.