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Building a sump

7K views 12 replies 2 participants last post by  SKAustin 
#1 ·
I am beginning to build my sump, and do not have a reef-ready tank. So this means I will require a external overflow. I see that all these skimmer boxes come siphon ready, but do any come pump ready? Is there a reason that I cannot find one that will pump water from the skimmerbox to the external overflow? It seems to me that a setup like this would be less likely to fail, without the risk of a siphon break and all...

Maybe if one doesn't exist for sale, suggestions on what to use to build my own would be appreciated.
 
#2 ·
Im not sure I follow your question here. By skimmer box, are you referring to the portion of the external overflow that sits inside of the tank and effectively surface skims the water?

Have you read the sticky on Understanding Sumps? I believe there is a section in there that covers the External Overflow.

http://www.fishforum.com/viewtopic.php?t=18777
 
#3 ·
I have read that article a few times now. It is very detailed and has helped with all the basic questions I had to get this thing started.

I am taliking about the Prefilter, as it is referred to in the article. My LFS guy calls it a skimmerbox. I want to pump water from inside the tank portion of the prefilter to the external portion of the prefilter. I don't trust a siphon. I have thought of dismantling a whisper HOB filter, and using the impeller and main tube to force the water over the back wall of the tank.

I included a picture from the article that I labeled to hopefully clarify the idea.
 
#5 ·
I see your issue now. Let me start by saying I run an external overflow on one of my systems, and have never had issues with the siphon breaking in the U-tube. As long as the flow in the u-tube is strong enough for any bubbles that enter to be carried all the way through the tube, there is little chance you will ever have a problem. They are really a lot more reliable than they may seem. There is however, an alternative to relying solely on the siphon, and that is to have a small water pump drawing water through a port in the top of the U-tube out, and back into the inner portion of the overflow unit. You can earch Ebay to find examples of these units.

Another idea is to buy yourself a reef ready tank, or if your tank is not made of tempered glass, have it drilled and build your own reef ready setup.

Personally, i think the idea you are entertaining is a recipe for disaster. If the pump output from your return line does not match the output from the pump you install in the overflow EXACTLY, you will end up with a flood. To install identically rated pumps would not suffice as the back pressure from gravity would slow the return line reducing the total GPH. Regardless even the difference of 1 cubic centimeter per day would eventually result in an eventual flood.
 
#6 ·
Thanks for the feedback.
I thought it could be a disaster, so I was going to install flow valves on each pump.
I like the idea of installing an air lifter to keep the siphon continuous, though. I found this on Dr. Foster & Smith, and think I can create something similiar.


Would a standard air pump help keep the siphon continuous?
 
#7 ·
wake49 said:
Would a standard air pump help keep the siphon continuous?
No. You need a water pump. An air pump would cause the syphon break.

Personally I still think this is unnecessary. As I said, as long as you have the proper flow, and the overflow box is designed properly, there is little chance you would ever experience a problem with siphon break. But you do what makes you comfortable. If the pump gives you the piece of mind, then it's worth it in my book. :) Good Luck.
 
#8 ·
I will try it as just a siphon for now. As long as that treats me fine, I will keep it that way. You sound like you trust it, so why not? I am going to get the prefilter and 15 gallon tank tommorow. What do you suggest for plumbing the sump? Is there anything I should know about pumps and such?
 
#10 ·
46 Gallon Bowfront. 1 Powerhead, I think it is a Koralia 3. Right now I am running a Fluval 305 canister filter. I have a stealth heater, keeping the system at 75-78 degrees. The tank is about 32" from the ground, and has a cabinet stand. I am picking up the fifteen gallon tonight. I was going to use a twenty, but it was too big to fit under the cabinet.
 
#11 ·
Well, I can give you a good number of pointers on building a sump, but for now; it's 8:15am and I just got home from work, so I'm a bit tired. Think of specific questions you might have regarding the planning and construction. In the meanwhile, here's a portion of an article of mine you may find helpful.

SKAustin said:
As with any project, it’s always prudent to start out with a well laid plan. Designing a sump that is appropriate for your needs, yet meets the necessary requirements for proper operation is by far the hardest step in the construction process. Consider your specific design needs, and keep in mind the following rules of thumb.

• Build the sump as large as you can possibly accommodate. The larger the better.
• Consider all of your needs before you start building. Moving a baffle sucks!
• There must be enough excess space to house any water that drains out of the display, the plumbing and the skimmer, in the event of a power outage.
• Inlet chamber need only be large enough to house the inlet pipes and the skimmer.
• Bubble trap baffles should be 1” apart (or more)
• Refugium section should house at least 10% of the display tank’s total volume. (55g tank = 5.5g Refugium)
• Return section must house enough water to cover 24 hours of evaporative loss without exposing the return pump.

Our plans today will be to create a sump with refugium from a 20 gallon tank, to be installed onto an existing 29 gallon system. The sump will need to accommodate a hang-on mounted Coralife Super Skimmer 75, heater and a 650gph pressure rated pond pump for the return. In addition to the Skimmer (or inlet) section, refugium, and return section, we will also be including a bubble trap between the skimmer section and the refugium. I have created a diagram as a sort of blueprint for the project. This will help in ensuring that the sump will meet the requirements necessary for proper operation.



We’ll take a look at each section in the plans, and how they work out. As a quick note, planning out a sump requires calculation of water volume. The formula to Calculate water volume is: (Height x Width x Depth) / 231 = Volume in gallons (measurements are in inches)

Inlet (Skimmer) Section
Since the skimmers optional “hang on tank” feature will be used to mount the skimmer to the side of the sump, The inlet section need only be large enough to house the inlet pipes, and the skimmer’s pump and outlet tube. I chose to make this section a bit larger to allow easier access for cleaning. The final measurement was 5”.

Bubble Trap
Bubble trap baffles are designed at 1” apart. The larger the gap between baffles, the slower the water will flow through the bubble trap. A slower flow through the trap would ensure that even fewer micro bubbles from the inlet and skimmer made it through the trap, but I chose to reserve more space for the refugium.

Refugium
Standards suggest that a refugium should be no less that 10% of the total volume of the display. Since the display is a 29g aquarium, that requires our refugium to be at least 3 gallons. By calculation, that requires a minimum of 5 inches of width for the refugium. I wanted the refugium to be much larger than that, so calculations were made for the return section first. That left 11.5” available for the refugium, providing a much larger chamber of nearly 25% of the total display volume.

Return Section
The return section needed to house enough water to cover evaporation for 24 hours without exposing the pump. The return pump stands only 3” tall, so to be safe, the minimum water level will be marked at 4”. By calculation, a return section with a width of 5” would provide a capacity of 2.8 gallons. Respectively, 1 gallon would be needed to reach the minimum 4” mark. This would allow 1.8 gallons for daily evaporation. Since my 55 gallon system observes a maximum daily evaporation of 1.5 gallons, I figured it safe to assume that the 1.8 gallon capacity would suffice. As it turns out, the maximum daily evaporation of this system ended up being just about 1 gallon per day, so my assumptions were correct (thank goodness).

The last thing I needed to consider before moving forward was if there was enough spare room in the sump to cover the drainage from the display and the plumbing in the event of a power outage. I calculated the amount that would drain out of the display tank would be about ¾ of a gallon. I conservatively estimated that the plumbing held less than ½ of a gallon. Therefore, in the event of a power outage, I would observe a 1” increase in the water level within the sump. This design provides an extra 3” of space above the highest water level during operation, which is more than enough to house the extra water.
 
#12 ·
Thank you.
My main question is the size of the plumbing. I work at a hardware store, so materials are easy to come by. What is the Diameter and type of plumbing to use? Should I use 1" Scheduled 40? Is CPVC alright? What kind of Solvent should I use? Is there one that is safer for the fish? And what is the best pump to use? Sorry if I am bombarbing you with questions, i just would rather do it right.
Thanks again.
 
#13 ·
Ive always used schedule 40 with standard solvents. 1" for the drain lines and 1/2" or 3/4" for the return lines. As for a return pump, I like the Eheim hobby pumps as they are quiet and the base has a place to mount suction cups for feet. The suction cups do a real good job of eliminating the noise caused by the pump sitting on the bottom of the sump. I currently use the Eheim 1260 for a 55 gallon tank with a 700gph rated overflow and they seem to be fairly well matched. If you are using a 500gph external overflow, you may want to use the Eheim 1250.
 
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