Need Help with 400gal w/d filter

[ethnics]

im getting frustrated sorta kinda. i recently aquired a 400gal tank with two 1.5" holes drilled in the back as n overflow. i know basically whats wrong with it but im wondering if there's any other way i can go about fixing this. pretty much im using a 1800gph pump on the 400gal tank for filtration. i can't get this thing dialed in to keep circulating... im using three 17gal bins for the sump stacked... top bin is filterfloss and 90% bio media. 2nd bin is all bio media. 3rd bin was the one that jus has water n the pump n heater. i filled the tank til it started to over flow. i filled the sump til it was almost full. i turned on the pump n bam, i grinned with happiness thinking im starting the cycle process. few mins later my sump is dried out... so i add more water to the tank, it starts overflowing again, it overflows so much my sump overflowed and now my carpets wet... i turn on the pump n my sump went dry again... damnit. is there anything i can do to make the overflow actually overflow or is my sump being 17gals of water basically not enough to keep a proper circulation going? i have a strong strong feeling its my sump being to small in total volume but i also thought it might be something with my overflow.

help plz. my babies would love to be swimming in this tank asap. thanks guys, you've inspired me so much in the past few months n pushed me in owning a monster tank.

 

[boisblancboy]

Kinda sounds like your overflow cant keep up with your pump and sump is going dry. With my system I fill the tank until the water starts running through the overflow and fills my sump, I let it then fill the sump about half way then start the pump.

You do have water flowing through your overflows right?

 

[mbutzer]

Your sump is too small. Have you calculated the volume of 1.5" of water in your 400g tank? I suspect that is more than 17g all by itself. You also need to add in the volume of water that would normally be in the overflow lines during operation, plus the water height you need in the sump to feed the pump in normal oepration, plus a safety margin should you have a power outage.

You could try looking at this for help, too... http://reefcentral.com/calc/sump.php

 

[Reiner]

As you already suspected your sump is way too small. I would try a minimum 60 gallon tank. What is the footprint of your tank? I have a 20 gallon on a 180 tank and had to slow down the return pump in order to not run out of water. Your sump is even smaller and the tank is a 400.

 

[boisblancboy]

You can run any size sump on any tank, though it wont do the job biologically. The water levels just have to get regulated first.

 

[ethnics]

im gonna go buy a 50gal bin n try that out. i calculated a 2" height in my tank to be about 25 gallons. so i need atleast a bin that will allow 25gallons of overflow when the power is out so the sump wont actually overflow. then water needs to actuallybe in there to keep the pump running. so im thinking a 50gal bin might do the trick. if it doesn't ill buy a 2nd 50gal bin and connect them some how. im to damn anxious n want this thing running already. right now i have 400gallons of still water sitting in the tank while im stuck at work!

 

[Reiner]

You post says that you have 2x 1.5" holes drilled as overflow. What is the actual pipe size that feeds your sump?

 

[ethnics]

You post says that you have 2x 1.5" holes drilled as overflow. What is the actual pipe size that feeds your sump?

its a 1.5" pipe. whatever the hole is it was previously drilled by the guy before me. the pipes feeding my sump is 1.5"