Not enough flow in 300g

[laz_dvl]

Here's the 411 guys and gals. I have a marineland 300g, 72l x 36w x 26h, with built in corner overflows(2x). The overflows are 1.5" reduced to 1" for the outtake, and return is 3/4" adapter to 1". I have 2 quietones 4000hh for return pumps. Now the question is my 2 overflows are not flowing enough for 1 single return pump. What can/should I do to have more flow from my overflows.

http://www.paradisepetshop.net/images/productuploads/6ftmonterey_25339.jpg

 

[Pharaoh]

I would look at trying to increase the sizes of the overflows to the full 1.5". You could try to get a different style of bulkhead that will allow you to increase the diameter of the return line.

 

[laz_dvl]

Sorry forgot to add, the tank is predrilled with 2x 1" holes in each corner. Drilled from the bottom

 

[Pharaoh]

I would look at possibly drilling the holes larger. Other than than, you are going to have to add on extra overflows to the tank.

 

[KaiserSousay]

Use all the pre drilled holes for the largest bulkheads you can put on. Use them all as intakes for your sump.
I lust for your tank, that`s going to look killer.

 

[Pharaoh]

BTW, is that what your stand looks like? If so, would you mind snapping a few pics of the doors, hinges, and such. Looking for cool ideas for the 500's stand.

Thanks

 

[RedTailKinG]

I need to ask do you have stand pipes in your overflows? if so remove them they also restrict flow sometimes

 

[hybridtheoryd16]

If your over flows have 2 holes in each one and you are using 1 for the drain and 1 for the input. Then make them both drains and add some over the back returns from the pump.

Also it looks like the stand is rather short. So if your sump is on the tall side and you have less than a foot of room from the bottm of the tank to the sump.

I could see that you would have to have a bunch of 45 degree angles to route the plumbing from the drains to the sump.

If that is the case then try switching to 2 sumps with a equilizer tube. And place them right below the drains. So it is a straight shot down from the drain.

Some under the tank plumbing shots my be needed to clearify the set up and give more options.

 

[laz_dvl]

Well I solved my flow problem,, by cutting a square opening in the overflow box lower then the original one and also instead of vertical notches for the strainer, I driled about 24 3/8" holes on 2 lines. Thanks everybody for all your suggestions/ideas.