Sump questions

[lilqtpierikki]

I am seriously considering making my own sump. That being said, HOW!?!?! Ok i have a layout of the sump being a wall, fuge in the middle, followed by 3 other walls, middle wall going from the top down. My main question is, i only have 23in under my cabinet. I cant find any premade tanks that small. So i was gonna make my own. I have a 55g so i was going to make a 20g. How tall should it be if i can only have a 23in length and how wide? Also i was planning on just putting the tubes straight into the sump rather than out the side. Suggestions? Lfs said i will probably have probs adjusing the flow to and from my tank. Is this true? Any help would be greatly appreciated!!

I was going to make the tank all of acrylic, is this right and how do i glue all the outside pieces together? Does it need to be reinforced? Thanks!!
~Rikki

 

[robert]

A sump is can be a nice thing to have, but isn't essential on a fish only tank.

Forget the baffles in the sump for a minute. I assume your tank doesn't have any overflows built in and that you'll be adding an overflow box to the tank.

An overflow box is a siphon. It requires a pump (an aqua-lifter or power-head) to get it primed. Water from the tank will flow through the overflow down to the sump, until the water level in the tank drops below the lip of the overflow box. The higher the water level in the tank, the faster water flows through the overflow to the sump.

In the sump, you will have a pump. It will pump water back to the tank at a fixed rate ~ say 600 gallons per hour. As the water level in the tank increases, the flow through the overflow will increase, until it matches the return volume from the pump in the sump. Provided the overflow is rated higher in gallons per hour, than the pump, the system will self regulate. Usually the return pump will keep the water level about a quarter inch or so above the lip of the over-fow box.

Now lets say the pump in the sump fails, get unplugged or something. The overflow will continue to move that 1/4 inch of water from the tank to the sump until, the water in the tank drops below the lip of the overflow box, at which point the siphon through the overflow breaks - but there is a problem. The hose/pipe that carries the water from the pump back to the tank will now act as a siphon too! To fix this, you need to drill a small hole in this pipe, about 1 inch below the lip of the overflow in the main tank. So the excess water capacity of the sump on a standard 55 gallon tank would be 47.4"(length) x 12"(width) x 1.25"(height of water above holes in return line) divided by 231 cubic inches per gallon - somewhere around 3 gallons. Your actual dimensions may vary.

Now what if the overflow siphon fails. The pump in the sump will continue to run until the level of the water in the sump falls to the point where the pump stops working. If your 55 gallon tank is filled to within 1 inch of the top, then it will only hold 47.5 x 12 x 1/231 gallons before it overflows. less than 2.4 gallons.

So you want to design your sump so that the chamber that houses your return pump prevents the return pump from sending more than 2.4 gallons back to the tank before it stops working. You adjust the baffle height and/or pump depth to accomplish this. Remember you need 4" inches or so of water in the sump for the return pump to even work.

Hope this helps some.

 

[lilqtpierikki]

Awesome thanks. I did know about the hole. Lfs showed me wht they were talkin about. What are the baffles for anyway? The pump i was looking at was i think $75 and i cant remember off hand how much they said the Gph was. Ill say 600. Is that good?

 

[bucksfan1976]

600gph is great for that 55 gallon. You know in my honest opinion if you know someone locally I would go and have the tank drilled, it opens up so many more posibilities. I had my 150 drilled and have not had one problem.

 

[lilqtpierikki]

i dont understand what you mean by drilling the tank.. my 55g or the sump?

also still wondering what dimensions are needed to make a 20g home-made tank. i may just try to google the answer...

 

[lilqtpierikki]

ok so this is what i found online:
Measure your aquarium from the left edge to the right edge. For example, my aquarium measures 18 inches.


Measure your aquarium from the bottom edge to the top edge. My aquarium is 12 inches.


Measure the aquarium along the side from the front edge to the back edge. Mine is 12 inches.


Multiply the three measurements. I got my small calculator and carefully entered 18 x 12 x 12 = 2592 cubic inches.


FINALLY multiply that number by 0.00433 to convert from cubic inches to gallons. I got 11.2 gallons of water in my aquarium.


This is my first idea but realized that 20in high is a bit too high... 23 x 20 x 10 = 4600 x .00433 = 19.918
2nd idea but i still think 18 is a bit too high 23 x 18 x 15 = 6210 x .00433 = 26.8893
Lastly 23 X 17 X 15 = 5865 X .00433 = 25.39545. I think I am going to use these dimensions for my sump

And i am going to use this set up: Sump/FugeThe length of this sump is 23.5 so I may do a 8" fuge in the middle. And add 6" on the inlet side because my skimmer is 5 1/2in wide...

Any thoughts or ideas. Are these good measurements?