good DIY wet/dry plans?

[pophead]

I'm looking for a good diagram or set of plans for a DIY wet/dry filter. I'd like to make one but I don't know how they work.
sorry I tryed searching but it's taking forever to find something.
some questions are:
do they sit under the tank? (I'm assuming yes)
what's a good pump to get the water back up?(it'll be for a 400 gallon tank)
how safe is it?
ty!

 

[cichlaguapote]

http://www.piranha-fury.com/information/article.php?id=27

 

[pophead]

thanks, good article.
so will the return pump will suck water from the bottem of the wet/dry?
how full should the wet/dry be when it's going?

 

[rallysman]

thanks, good article.
so will the return pump will suck water from the bottem of the wet/dry?
how full should the wet/dry be when it's going?

make the water level stay at the bottom of the bio media.
As long as your overflows handle more than your pump can flow, it's easy to regulate water level.

 

[pophead]

ok, thanks. how big of a tank would be needed for a 400 gallon tank? I have a spare 15 gallon hex but I'm guessing that's too small. something like a 30-40 gallon?

 

[rallysman]

I use a 75 gallon sump on my 265, and a 55 for my 300. I think you could easily get away with a 55, but I wouldnt go any smaller. You need to be sure that if you lose power, the overflow from your tank wont be too much for your sump to handle.

 

[eh1421]

whats the diminsions on your 400 gal tank
you need to know this
take the length x the width and then calculate how much water is capable of going down the overflow.
almost always around 2 inches on a 1 inch overflow
use this to determine gallons
http://www.firsttankguide.net/calculator.php
remember you have to figure out the amount of water that is already in the sump

hope this helps

mike

 

[pophead]

ok so 55gal it is. it would work to put the drain 3 inches down, since 3 inches of water in a 104" x 36" (approx the size I want to build) is about 48 gallons, so that leaves me a little bit to work with.

 

[rallysman]

your water level will stay at the overflow level, so make them where you want the level in the tank to be.

 

[CHOMPERS]

I did the calculations for Milkmans tank and it needed a minimum of 45 gallons of surge volume.

The formula in inches is L/12 x W/12 x D/12 x 7.5 = gallons in tank