Help on building sump.. first big tank:)

[easydoesit]

Okay, I'm getting my first kind of big tank. 150 gallons... Craigslist of course lol.

http://nh.craigslist.org/for/672423827.html

He/she's selling me the tank and stand for $300.00.
The tank is going to be for my Oscar+a couple more Oscars. As close to an Amazon Biotope as I can get. My O is in a 55 right now and hes about 5.5", growing pretty quick. The dimensions on this tank look nice for a few Os, plenty of turnaround space.

There's 2 holes drilled in the back for an overflow.
I'm planning on using my 55 gallon as a sump plus my 2 Penguin 300(350? i dont remember..the kind with 2 biowheels)HOBs for extra filtration/aeration.

I need some help and suggestions on building the sump. I have a general idea. For supplies I'm thinking I need:

2 bulkheads to fit predrilled holes
1 powerful powerhead
Tubing to connect the bulkheads to the powerhead/sump itsself
Filter media: sponges, scrubbies/lava rock, filter floss etc.


I don't know how to match the overflow rate with the powerhead GPH rate(or will the overflow rate be the same as the pump rate? yeah that sounds right).. do I just fill up my tank, fill up my sump and turn on the powerhead and it will start and even out like that?
How many GPH for a powerhead should I be looking for?
Any suggestions on powerheads that would be good?

Yikes, I don't think it's as easy as I thought it would be.
any help, advice, tips, suggestions and even links would be nice.

thanks in advance

 

[japes]

It's quite simple.

What you need to buy looks good, though you'll find yourself possibly need more bits here and there.

Please note I am not talking from experience here, if it's simply a gravity fed overflow then it's different to my setup.

You're going to need to work out how fast the tank will overflow, you can do this by blocking the overflow holes, filling the tank up to it's maximum capacity, then letting them drain into a bucket. say you're using a 2.5G bucket, you measure how long it takes to drain 2.5G, then do the appropriate calculations, so if it takes 30 seconds, it's doing 5Gallons per minute, then times that by 60, 300 Gallons per hour.

Then you need to research your pumps, find something that is has a slightly lower flow rate than your overflows at head height (all good pump manufacturers will have a graph that shows you how flow drops as the height of the tubing rises). The overflows will control the level of your water, so it will drain out until it can't drain any more. With it pumping back in, if the pump is slower (or you can limit a faster pump if you really want), the water will stop draining until the pump catches up.

This continues constantly meaning neither the sump gets drained dry, nor the tank overflows (as a result of the overflows not keeping up). That's the basic gist of it.

 

[easydoesit]

Thanks, couple of Qs..

You're going to need to work out how fast the tank will overflow, you can do this by blocking the overflow holes, filling the tank up to it's maximum capacity, then letting them drain into a bucket.

Then you need to research your pumps, find something that is has a slightly lower flow rate than your overflows at head height (all good pump manufacturers will have a graph that shows you how flow drops as the height of the tubing rises).

When I do the test for overflow GPH, should I open up both of the holes to drain into a bucket, or just one of them?

About how much slower should the powerhead pump than the overflow?

 

[japes]

Thanks, couple of Qs..



When I do the test for overflow GPH, should I open up both of the holes to drain into a bucket, or just one of them?

About how much slower should the powerhead pump than the overflow?

Do both, you want to get it as accurate as possible. Up to you, obviously more flow is better, so if you're draining at 600gph I'd aim for a pump with 550gph at head height.

Edit: Or there's a thread here about reducing the flow of your pump if you miscalculate or decide to use a more powerful pump.