Plumbing dual overflow question

[ronkent]

So I just upgraded my 55 to a 125 dual overflow. If i run just one over flow everything works flawlessly. Nice and quiet. If i try to run both overflows they alternately overfill(not overflowing the overflow area)and drain below where the should but gurggling at the moment it get below. Its really hard to explain but just imagine its like a set of scales constantly going back and forth from one overflow to the other. 1 rises, the other falls, back and forth. What would cause this? Someone else made 2 suggetions: 1. The return pump(Mag 9) is too small. or 2. Both of my drains connect via a T. Maybe i need to make each overflow flow into the sump separately. Any Ideas?

 

[teo241]

i think it may be the fact that your drain combines into a T. i have a 120 with dual overflows, which both drain separately into the sump, and i've never had the "bouncing" effect you are getting between the overflows. separating the drain will likely help your problem, and it provides some insurance--in case one of those drains becomes blocked--you have a separate one to handle the flow. and with the pump you are using, one pipe can easily handle the flow.

i'm using the same pump (mag 9.5) as my return pump from my sump, so i doubt this is the problem.

 

[blstravler]

TEO241-

YOU ARE SO RIGHT !!!!

That is about the insurance and a possible clog. I had a large anthias some how make it pass the top of my over flow and get sucked into the return pipe and get glogged after the T. I run a 3.5k gal/hr return pump on my 180. I don't think I need to explain any further. As well the 25gal of make up water on the auto top off switch also ended up on the floor.

Needless to say I made the plumbing change.

 

[ronkent]

Ok i will have to get an elbow tomorrow after work and try it out. I capped the other drain for now. Thanx

 

[Scuba_Dave]

Yup, both of my drains are totally seperate all the way to the sump. Other wise you cut the capacity down