Call for Help - Sump Design (long)

[newsalt]

I want to use a sump on my new 120g. I'm very reluctant because I'm deathly afraid of a flood. The tank is in our family room with a new carpet.

The tank is not drilled and I was going to to make my own overflow. I have a spare 20g long tank I was planning on using. From what I've read, 600gph seems to be a good flowrate from the overflow. I used the "overflow calculator" on RC and it says I need a 1" dia. drain pipe for 600 gph. That's great. It also says I need 9 linear inches of overflow. I understand that too, but what about the teeth? The overflow I was planning on making would be black acrylic with "teeth" on three sides. One thing I don't know is how many teeth does the overflow need to give it 600gph capacity and what are the width and length of the teeth.

To maintain the siphon in the overflow pipe I was going to tap into the overflow pipe at the high point and attach a piece of tubing from that tap to the venturi connection on a powerhead that will be in the sump. Good idea? Also what diameter does the pipe that brings the water from the overflow to the sump need to be? Is the 1" from thr RC calculator correct?

Next confusion: If the overflow is delivering water to the sump at 600gph, then the return pump needs to also be 600gph max. If it's more then you'll be returning water to the display tank faster than it's overflowing and the display tank will spill over, right? The height from below my cabinet to the top of the display tank is about 4 ft. I have to take that "head" into account when I size the return pump as well as losses in the return piping and fittings, right? But what about the baffles in the sump. Do you have to account for losses as the water goes over and under baffles? If you do, how do you do that?

Baffles in the sump, that's yet another question. How many do I need and how tall are they? I'm not planning on a fuge in the sump, so my first guess is I need three baffles. These are the kind of questions I have. Can help me?

Thanks

 

[jhale]

new salt, you have to check out marcs site, http://www.melevsreef.com/

it has all the info you will ever need on sumps, how they work, and how to make them. enjoy!


site index http://www.melevsreef.com/links.html

 

[kimoyo]

newsalt - the point of a sump, IMO, is to filter your tank water with a skimmer. The benefits is you have less water level fluctuations in the display tank, you increase your water volume and potentially you increase dissolved oxygen.

If the main goal is to clean the water with a skimmer than you want as much skimmable dirt to get to it as possible. That skimmable dirt will float to the top of your display tank and create a film. The point of having a certain amount of linear inches to the overflow is you want to drain as much as possible of this top thin layer of film to the sump/skimmer. You could make your overflow very narrow and teeth very tall but then you wouldn't get as much of the dirt/film from this thin layer on the top as you could.

You want your return pump to pump less water than the max your overflow/overflows can handle.

Can you explain why you need a siphon? And then we can go into if you will need baffles.

1" pipe is good for 600gph, it can even handle a little more but 600gph is what is recommended for safety.

 

[newsalt]

Can you explain why you need a siphon? And then we can go into if you will need baffles.

Whithout a siphon, how will I get water into the sump?

 

[kimoyo]

Whithout a siphon, how will I get water into the sump?

You can do it with air also, which is what most do.

If you have one drain you shouldn't do a siphon (without air). If you have two drains you could do a siphon.

The durso standpipes mix air with water to drain the water to sump.

The problem with a siphon is you have to match the water flow down the drain to exactly what the pipe can handle (since only water will flow thru the pipe). If your return pump is too slow the water will drain to fast, suck air and gurgle. If your return pump is too fast you will flood your tank.

IMO, setting up a siphon is the best route but you need two drains (one as a backup). Doing a durso causes bubbles to enter the sump and noise issues. A siphon will be silent and no bubbles (no need for baffles). If you can have two drains (return over the side or drill a third hole) you can try to match the the return pump to the drain pipe size (if your doing a 600gph siphon you will want to use a smaller pipe than 1") but it will be hard to get it exact. The second drain allows you to try to match the flow without fear of flooding. You match flow by using a gate valve on the return (which I prefer) or the drain itself. You set it up, watch the second drain and tune the valve until no water comes out of it.

Look up Herbie's S.O.S (silent overflow system) on RC.

 

[Tonyscoots84]

if i was you i would def. stay away from the overflow espescially for a 120 gallon but u already have livestock in it. if you do go with a hob overflow your gonna need to care for it at least 1x a week. or every other week. also what i would do if i was you i would do a bigger sump. at least a 30gallon or up. just my recc. to you.

 

[kimoyo]

if you do go with a hob overflow your gonna need to care for it at least 1x a week.

Newsalt - are you planning on doing a hob or drilling the tank?

 

[Nsr250NYC]

Not to hijack your thread newsalt, one quick question. what's the proper size for the return pipe for an internal overflow? i know it's 1.25" drain for 1" bulkhead. and what size pvc pipes should be used beneath the bulkheads to the sump? both drain and return. sorry Newsalt, dont mean to hijack.

 

[kimoyo]

Usually the drain pipe is bigger than the return because you always want to pump less than what your drain can handle.

But the size of your return really depends on the pump you will use. Some pumps need 1.5" for full potential and others just 0.5". That said, its better to have bigger return piping to help with head pressure. But personally I wouldn't go past 1" unless my pump needed it.

 

[House of Laughter]

Newsalt,

if you are worried about flooding your carpet, you may want to consider not doing DIY. Not that it won't work, but more times than not, as you are learning and building, you are making mistakes which leas to floods - unless, of course, you are great at DIY and follow trusted formulas.

Good luck with it and welcome to manhattanreefs.

House

 

[Chiefmcfuz]

House if he choses to not DIY who could he get? I have been looking to buy a premade sumpfor a while but can't find one.

 

[noodleman]

kimoyo, when he's talking about a siphon in the pipe, I think he's refering ot the U-tube not the actual pipe going form the overflow to the sump.
Newsalt, the baffles and everything inside the sump itself depends on what you want to do with the sump, for example do you want a refrigum in there or other stuff, etc.