Unusual sump design. Thoughts?

I'm working (very slowly) on a 55-gallon tank setup. I'm currently getting the shelves in place that will hold all of my tanks, and I've realized that I have enough room to put the sump behind the 55gal rather than under it. In fact, it would be much, much easier to do it this way.

So what I'm thinking is, instead of doing a typical overflow, I could simply place the sump (5-10 gal tank) so that the water surface in the sump will be on the same level as the water surface in the big tank. Then, I can run two siphons between tank and sump -- one for inflow, one for outflow -- and place a powerhead in the sump on one siphon to drive water from the sump to the tank. The other siphon will equalize the water levels, pulling water back into the sump.

My question is: is this feasible? What concerns should I have? Any thoughts?




EDIT: I suppose I'll need a larger pipe diameter for the unpowered siphon... right?

 

HI aylad,
Interesting concept.

My first observation, it will be very difficult to establish a siphon since both tanks would be the same level; a siphon relies on gravity.

As to the feasability, yes, I believe it is feasible. I have few thoughts on how it might work, and can probably knock up a 'concept' drawing tonight when I get home from work.

 

That'd be awesome, thanks.

 

Just read through your post. I have a couple thoughts. Siphons rely on gravity, the larger the difference in water level the faster the flow rate. I understand the reason to ideally have the water at the same level. I would assume it is so if your pump stops, you don't have 55 gallons of water on your floor. (I know this should never happen as the siphon should only be a couple inches or so under the water line.)

My first thought would be that you would absolutely need to make sure that your outflow siphon can flow more than your powerhead can pump. If it was me I would aI'm at double the rate, because inevitably you will get some sort of build up that will reduce the flow. Or to be extra safe use two outflow siphons that flow at least as fast as the pump. If you do that I would say one should extend a couple of inches extra below the waterline of your tank, incase you lose the upper siphon.

My second thought is more of a question as to the design. It almost seems like you are trying to build a 5-10 HOB sump. Now I don't think that is such a terrible idea. I also understand that is not exactly what you are doing, but its not far off. I would suggest you at least think a bit about that. It seems like it would be very quick and easy to modify a small acrylic aquarium to be a giant HOB filter or build your own DIY glass one.

I actually just had one more thought while writing this, but either way you do it your sump will not keep the water level in your main tank constant. You could build an internal, drill less overflow box if you have any concern to keep the main tank level constant. My first thought on that would be a fish bagger like the use at any LFS I've ever been in (as well as the big chains). I would just drill some holes around the edge or cut some slits into it so that you can just hang it on the inside of the edge of your tank to act as an overflow box.

I hope that helps a little, and I am interested to see what Ryan turns out.

 

Just read through your post. I have a couple thoughts. Siphons rely on gravity, the larger the difference in water level the faster the flow rate. I understand the reason to ideally have the water at the same level. I would assume it is so if your pump stops, you don't have 55 gallons of water on your floor. (I know this should never happen as the siphon should only be a couple inches or so under the water line.)

My first thought would be that you would absolutely need to make sure that your outflow siphon can flow more than your powerhead can pump. If it was me I would aI'm at double the rate, because inevitably you will get some sort of build up that will reduce the flow. Or to be extra safe use two outflow siphons that flow at least as fast as the pump. If you do that I would say one should extend a couple of inches extra below the waterline of your tank, incase you lose the upper siphon.

I'll definitely use a larger outflow (tank-to-sump) pipe, since the water flow through that pipe won't be powered. I've also been planning to use two outflow siphons for safety. I'm glad your thinking matches mine, though.

My second thought is more of a question as to the design. It almost seems like you are trying to build a 5-10 HOB sump. Now I don't think that is such a terrible idea. I also understand that is not exactly what you are doing, but its not far off. I would suggest you at least think a bit about that. It seems like it would be very quick and easy to modify a small acrylic aquarium to be a giant HOB filter or build your own DIY glass one.

Aha. I didn't explain myself particularly well in my original post. The original plan was to convert a 10gal tank to be the sump container. I'm thinking now that I might go smaller, but the general idea is to use something other than a pre-built sump.

I actually just had one more thought while writing this, but either way you do it your sump will not keep the water level in your main tank constant. You could build an internal, drill less overflow box if you have any concern to keep the main tank level constant. My first thought on that would be a fish bagger like the use at any LFS I've ever been in (as well as the big chains). I would just drill some holes around the edge or cut some slits into it so that you can just hang it on the inside of the edge of your tank to act as an overflow box.

Okay, that's an interesting thought. I could do that, sure. Do you think there would be a lot of variance in the main tank water level, or would it just be kind of gentle surges? I hadn't expected problems with this, but then, I have no experience with sumps.

I hope that helps a little, and I am interested to see what Ryan turns out.

It is very helpful, thanks, and I can't wait to hear from him, too.

 

Okay, that's an interesting thought. I could do that, sure. Do you think there would be a lot of variance in the main tank water level, or would it just be kind of gentle surges? I hadn't expected problems with this, but then, I have no experience with sumps.

A lot, I would say no. With the design you're thinking about you might get gentle surges. Either way depending on how you have both covered and what kind of environment the tanks are in you could get a lot of evaporation. In my old uncovered 24 gallon, 24"x12" footprint, I could loose a gallon a day to evaporation. It was just something to thinking about depending on how showy you want the tank to be.

 

I'm planning DIY glass sliding lids for both tank and sump, if possible. Some kind of lid on the sump, even if I can't do glass.

 

I don't see any reason to not go with glass on the sump tank, unless it is a weird shape.

 

Yeah, it's just that I'm re-thinking my commitment to using a tank. It might be some other container. Not sure yet.

 

Sorry for the bump, did you end up getting any further with this project? It got me heaps interested reading through these posts

 

Sorry for the bump, did you end up getting any further with this project? It got me heaps interested reading through these posts

Still in progress.

More accurately, I'm still building the shelves that will support my tanks.

I'll be sure to post photos and thoughts once I've actually set this up... probably in a different thread, though.

 

CPR makes a refugiem that hangs on the back of the tank. These are mainly used for saltwater tanks but the idea could be adapted for freshwater. They have a powerhead pump water from the main tank into the smaller tank with a gravity return line..