Need Info on Overflow Box and Sump

[PaulineMi]

Other than reading enough to get kind of confused I'm clueless regarding a sump/overflow box. First, I'm not drilling my tank, second, no DIY talent here.  And I really need to apply the K.I.S.S. approach to this. I get easily confused. 

That being said what I need is a higher volume of water for my 90 gallon tank. I think that can be accomplished by running water through a tank below my 90 (I have a spare 55) utilizing a "hang on" overflow box.  Something like this: http://www.drsfostersmith.com/product/prod_display.cfm?pcatid=18358

Since that's the extent of my knowledge can I get some input regarding what I need to consider to do this? Can it be as simple as water overflows into the box, runs down into the tank below, then the pump runs water back up into the tank?

How do i prevent flooding with incorrect water levels and do I need media in the 55 under the main tank?

I was "gifted" some extra discus with my recent order and now have 10 of them. I was planning on eight for the 90. I'm thinking I can increase my fresh water for them this way. I do have a HMF filter running in the tank and a seeded filter for the set up.

[BallAquatics]

How do i prevent flooding with incorrect water levels and do I need media in the 55 under the main tank?

Typically with an overflow system, when the pump quits pumping water into the upper tank, the water level in the upper tank stabilizes and the overflow simply stops. In other words, no flooding problems.

You might consider emailing Stephan for suggestions, he's the master of filtration!

Dennis

[PaulineMi]

Good idea Dennis. 

And I can also ask him what size air pump I should be using for my HMF filters.

[Frank The Plumber]

There will be a certain amount of water in motion that has to be accounted for. As an example let's use a 55 gallon tank 12" x 48" of surface area. With a skimmer or over flow into a sump or reservoir style system we will have a certain amount of water in motion. If we have a level of water that is 1" above the over flows box and drains 1" from the tank prior to not letting water out we multiply 1" x 12" x 48" to get the capacity of the reservoirs overflow capacity. In my example the number is 576 cubic inches of water. We then calculate the amount of water in transition. This is the water in both the return and effluent (water to sump) tubes. We need the capacity o the box used for the skimmer, get to cubic inches by multiplying height x width x length to get cubic inches. The length of the tubing x the diameter, convert this to cubic inches. We then add all of these cubic inches together to get a total amount of cubic inch displacement. This gives us our total number of cubic inches of water in motion by volume. If we have a skimmer box that is 8" x 8" x 12" tall it would have a maximum displacement of 768". If we have 12 feet of 1" tubing we have 12x12x12 , 1728 cubic inches. We then add these numbers. 576+ 768+1728= 3072 inches of volume in motion.

A 55 gallon aquarium holds 11,520 cubic inches of volume.
A 20 gallon aquarium holds   4,608 cubic inches of volume.

If we choose to us a 20 gallon aquarium as our sump reservoir we must figure out the operating height of the water, the amount of water in the sump to operate the pumps with a buffer zone so as not to have to add water daily. Let's use 4" of sump height. 4x 12 x 24=1152 is the volume required for operation.

Add 1152 and 3072 inches =4224 cubic inches of water, the capacity of a 20 gallon aquarium is 4608.
The next item to consider is displacement within the sump reservoir. If we place media or items within the water w consume volume capacity in the sump. Ideally we only want the pump in the reservoir the media should be suspended above the reservoir waters and only require minor supports that will go into the water.
If we keep or total amount of items in the reservoir below a 400 cubic inch total in volume we can use a 20 gallon tank.

We like to use the tubing as filled both in and out and the skimmer box as filled to provide a forced buffer into the equation, this gives you a bit of error capacity. We over equate the volume on these two items by a bit. If you can calculate a maximum water height operating line of reference into the sump that will help to avoid over filling the sump. If we run the sump at 6" instead of 4" we push the volume numbers over the design and could have an overflow.

There are a few ways to compensate for sump reservoir dimension. If an under sized reservoir is required an over flow drain may be plumbed into the sump. If the height rises beyond sump capacity it simply drains away. This does create a situation in which required capacity for operation occurs. If you lose enough water the system will not self restore itself to normal operation. In this case a flow check valve may be used. This method employs a float valve plumbed into the side of the sump box or built onto or into a fixture to allow the float device to open when the required amount of water  volume is not enough to self start. When the system kicks in the sump will drain below the height needed to operate, as it does the float will drop and allow water from any chosen source to enter the sump and restore or maintain operating volumes.

It is good practice to plumb air flow into a media box within a sump. This will keep the matrix alive in cases of flow loss or flooding and aide in polishing the effluent waters in normal flow operations.

These guys have some toys for a system. www.aquacave.com

[Mugwump]

LOL....now post that again in English....hehe....I know what you're saying, but what would your explaination be in layman's terms.??

[PaulineMi]

Thank you Mr. Mugwump.  I was starting to glaze over even though it's a great explanation. Lol.

But thanks Frank.    The Eshopps one on the Aquacave site was one I was looking at.

[Frank The Plumber]

Hmmm.

This is actually about as simple as the explanation for the proper calculations for a fluid system in motion can be. Sorry.

Maybe I can explain the what happens so you get an idea of why we have to calculate this.

A properly sized system will flow nicely, if the power goes out it will fill to a certain height but not over flow on the floor.

An improperly designed system will over flow if the pump stops running. A certain amount of the water will dump out onto the floor, when the power fires back up the pump will not be able to have enough water to put the filter back into service. You then burn up the pump or it never does start back right again and you have dead fish.

I have seen a lot of folks with a 15 gallon sump under a 75 gallon tank. That won't work. Unless the surface area is only 12x 36.

Maybe I can explain the parts you are glazing on or simplify those. Sorry.

[Mugwump]

No need for sorry, Frank...you're right, a person needs to know the sump capacity in relation to the tank volume. Isn't there a 'German' overflow ststem that has a hole drilled in the overflow tube, thus stopping the drainage to the sump in case of a failure ??..or is it for something else..?
...

I think it's mentioned in this threads video...
http://www.mugwump-fish-world.com/index.php?topic=845.msg7791#msg7791

[BillT]

LOL....now post that again in English....hehe....I know what you're saying, but what would your explaination be in layman's terms.??

To sum up my understanding of the interesting overflow/water in motion part of Frank's explanation, without the math:
One common failure mode is the pumps stops for some reason:
If you look at the overflow box in the link http://www.drsfostersmith.com/product/prod_display.cfm?pcatid=18358, you'll see that the siphon from the tank goes into a part of the box separated from the box drain by a divider. This acts as the final overflow controller of the whole tank. If you just had a siphon going down to the sump, the tank could drain down until the end of the siphon inside of the tank sucks air, breaks the siphon, and stops. With the overflow box, the siphon can drain the tank only as low as the divider level in the box. Since the siphon tube extends below that level the siphon should be preserved if everything stops. The water above this line is some of the "water in motion". This, along with the volume of water in the pipes (tubes), is the water that will fall down into the sump should the pump turn off. The sump should either have enough volume above its normal water line to contain this "water in motion" or be "plumbed to a drain (usually a floor drain)" to handle this potential excess volume. Alternatively, you could have a second pump that will turn on if the sump water level raises and pump water out to some acceptable place (like a sink). Sumps pumps (found in hardware stores) are set-up to do this, but may not be good for fish exposure. Otherwise you can get water in the wrong place.

The siphon may fail for some reason (maybe you cat grabs it or something):
This is a reason to prefer a drilled tank over overflow boxes. In this case the pump will continue to pump water into the tank draining the sump. The tank, not having the siphon as an outlet will then overflow.
If the pump is set-up to turn off depending at low water levels in the sump, the amount of water pumped out will be reduced. This will also keep the pump from pumping without any water which usually kills pumps.
If the pump is also wired up to stop pumping when the water in the tank is too high, it should prevent any over flow.
It is also possible to trigger an alarm in these conditions, but each of these steps just gets more and more involved, more costly, and less easily available as an off the shelf solution.

I use the following:water going to sumps controlled by a float valve to keep it filled under normal conditions (water demand (leaks and evaporation) not exceeding what can be supplied), an over flow to drain via a sump bulkhead (drilled) and a pump pumping water up to the tanks that gravity drain back to the sump via drains drilled through the tank walls. Also my pumps will turn off if the water in the sumps gets too low.
Leaks can still happen if the tubes or pipes going to the tanks are misplaced or break or the tank drains can get clogged. This could result in leaks and drain the sump until the pump gets turned off.

No system will be perfect, but in none these cases will all the water go out of the tanks and leave your fish dry. In tank filtration and aeration should keep your fish environment in reasonably good condition until you notice things and can fix the problems.
Food in makes for fish waste out (into the water). If you are having a filtration problem it is often best to just stop feeding until the problems is resolved.

[PaulineMi]

Frank...first of all I do appreciate the explanation.  I've been doing so much reading on this that it's just boggling my mind. I didn't mean to sound ungrateful.

Bill....I'm not having filtration problems or overfeeding issues.  I've read where people set up an empty tank underneath the tank with fish to increase the water volume.  That's what I'm interested in doing.

I just got a new 90 gallon for what was going to be my 8 discus. I was sent some extra discus so now I have 10. My thoughts were that I could put the 55 under the 90 and simply circulate the water. I'd then have 145 gallons of water for the fish. Is this doable? From all of the reading and "you-tubing" I've done it seems to be uncomplicated but I just needed some additional step A, B, C info.

[BillT]

No problem Pauline.

You certainly can increase the amount of water in the water system your fish are in by linking another water container (like a sump) to it and circulating the water.
The likelihood of it leaking involves details of plumbing.
My comments about food and filtration were intended to address what might happen if the sump (where filtration is often located) is not functioning properly.

Some people think that water volume that the fish would not be swimming through is not such an issue if your filtration system is large and mature (meaning has many kinds of different bacteria not just nitrofiers. The larger body of water is often considered good because it can further dilute wastes. Another argument involves the dilution of growth limiting fish pheromones, allowing the fish to grow better. Although I have heard about these pheromones for many years, I have never met anyone able to give me a real reference to them. If these pheromones exist, a large and mature biological filter would probably have an obscure kind of bacteria in it that could eat the pheromones. The extreme example of this would professional aquaculture water systems that can raise food fish at about 1/4 pound of fish/gallon.

[PaulineMi]

I've heard the growth hormone theories also.  I have a large HMF filtration set up in the 90 gallon tank and a fully seeded HOB filter will go on it for awhile. I can also leave the seeded HMF foam that's currently in the 55 in that tank when I convert it to a sump.

I just found out that the guy who built my tank stand has a 90/55 set up with an overflow box and sump. He's giving me info and pictures on what I need to do, including water levels.

So....I feel the tanks will be okay biologically.  I just want more water without having to replace two new tanks.  I already screwed up on the air pump I bought.

Whew. I'm ready to get this done and just be able to sit back and observe my fish again.  My rocking chair, iPod and a glass of wine are calling to me.

[Frank The Plumber]

It's sort of tough to design the system without the calculations. It is a lot to take in and there are a lot of variations and opinions. In general you just really want to be sure that the concept and math works before you spend towards equipment. Most folks on't find out the numbers were wrong or the design was faulty until the hard wood floor is trashed. snicker.

The thoughts on the growth inhibitor is that it is a synthesized protein waste product. Perhaps a component of uric acid. It is thought that this inhibits the ability of genes to replicate quickly efficiently and to their best potential. If we look at stem cells we see that they have the capacity to become many different cells at various times during the growth stages. During this time a number of triggers interact with the stem cell genetics as they set towards their permanent forms. It is thought that these triggers are interfered with by having poor environmental conditions. With the triggers either inhibited or over stimulated we lose the capacity for the gene to sequence towards it's final form.

I had a few conversations about tissue engineering with the girl, pretty fascinating stuff.