Plan For Moving Filtration to Basement

[amahler]

Hello!

I've been pondering the idea of turning an old glass 90 gallon aquarium I have on hand into a large sump for my 90 gallon acrylic system (nearly double my water volume this way) while simultaneously moving it all to the basement.

This will require plumbing through the floor and a decent sized pump.

I'm looking at about 22 horizontal feet of pipe, a couple of 90 degree elbows, some couplings and about 11 feet of vertical distance.

I ran an approximation of these variables through this pump calc:

http://reefs.org/pumps/

I based it on an Iwaki MD-100 model pump. Depending on my pipe size (3/4" vs 1") I can get anywhere from about 1000 GPH to 1400 GPH (give or take) using this design. Currently, I'm probably getting about 450 GPH with my existing pump under the tank, so this would achieve my goal of moving to the basement AND upping my cycling rate.

I made some 3D models of the house, the tank, the sump system, etc., so I could visualize the idea and look for problems.

I was hoping to get some feedback on this design from any fellow aquarists with experience in this kind of endeavor.

Any comments, suggestions, hardware recommendations, etc., would be highly appreciated.

The 3D models are visible here along with a Quicktime animation I threw together that flies through the entire design from various angles:

http://sparhawk.sbc.edu/basement-sump

Thanks!
- Aaron

 

[ellisz]

Nice work. That looks great.

Only thing I could add is make sure your sump room is well ventilated. Humidity will be an issue. You will also need something in the sump on the drain or some baffles in the sump. The velocity of the water coming down will create a lot of bubbles.

Also, I assume your overflow can handle the huge increase in flow. The standard Magaflow won't handle 1400 gph.

I have a GenX PCX 40 on my basment sump. I only have to pump 12-14ft though and my tank flow I estimate to be around 600-800 gph. That is what my overflow handles.

Looks good.

 

[amahler]

My tank is acrylic and has an overflow box built in. That serves the current sump in the form of a single large hole (1" to 1.5", it appears) in the bottom of the back left corner.

I've been curious about that aspect, actually. I assume this means that I'll not be getting enough water out from that hole to keep up with pumping it back in so fast? If that's the case, I suppose I'll have to forgo the massive GPH and just throttle my pump back to whatever I can get away with? Since my pump is not throttled now, does that mean my current GPH is as much as I can ever do?

How would one go about computing that or possibly even increasing it?

Thanks!
- Aaron

 

[ellisz]

From what I understand, the standard overflows that come on All Glass tanks are rated at 600 gph but it is limited by the overflow wall design, not the size of the drain hole. If you don't know the rating on the overflow, you might have to do some testing and see if you need to throttle it back.

Maybe someone with a big pump can chime in.

Your current overflow will most likely handle a bigger pump but since the pump is supplying water at 400 gph, the overflow is only flowing 400 gph. Pump selection should be based on overflow capacity. You can always under size the pump but you can't over size.

I have heard of people taking the rated 600 gph overflow like I have an modifiying the overflow so it will handle 1200 or so. I did some modding on mine but I have no way of testing what gph I am getting. You might be ok. Depends on your overflow.

 

[amahler]

On an added note, I just looked closer and the outside diameter of the threaded bulkhead connector sticking out of the bottom of the overflow in the back left corner is considerably larger than the diameter of the pipe that stands in the box itself. It appears that pipe steps down quite a bit and the hose underneath that leads into the current wet/dry is slipped into this bottom hole rather than screwed onto the outside threading.

My point is that the hole from the overflow box in the bottom of the tank might have a good bit larger usable diameter than the plumbing currently hooked to it for today's outflow rate.

However... even if I were to switch all of this plumbing to use the full diameter, will the overflow of the tank through the "teeth" cut into the top two sides of that corner overflow box not still restrict the flow?

Where is the true limiting factor here and how would I compute the absolute maximum rate if that's what I'm not already getting?

Thanks!
- Aaron

 

[Brisc0]

Just brainstorming, you'll have to think it through as far as plausibility. to defeat the overflow issue you could "help it along' with another pump upstairs that feeds a larger diameter line from your overflow. (i.e. your overflow has a junction where it still drains to the basement, however another pump pulls water from your main tank and feeds it to the overflow line to "makeup" the remaining GPH) I would think that this could work, it just transfers the responsibility of moving water from the main to the sump to another pump and puts the overflows job solely to skimming the top. Anyhow, just a thought, never done it, never seen it done, take it with a grain of reef crystals.

 

[amahler]

Elisz,

Seems I was writing as you were writing, so we've collided slightly on my premature questions and your answers.

Thanks!
- Aaron

 

[amahler]

Brisc0,

Thanks! It is an interesting idea. The only downside I can see right up front for my purposes, though, is wanting to move all the noisy gear into the basement. On that basis, I don't know that I want to put in a second pump near the tank.

I'm thinking I might be "hosed" here (pun intended) on the overflow limitation. I can still proceed with this, but I might not be getting my cycling rate up by much (if any). Oh well. I will write to the designer of my tank, though, and see if he has some hard numbers. He's been VERY helpful in the past on other questions (myfishtank.com).

Part of the reason I don't know these specs up front (I'm usually pretty anal about knowing all the specs and possibilities of any kind of system that I get into) is that the tank was given to me by a friend in its current running configuration. Had I bought the system originally for a reef design I might have had it designed differently and likely come across this during the initial research. Granted, I'm not complaining here at all... it's a wonderful system and FAR more expensive than I'd have pursued (if I had bought anything at all) at this point in time.

Whatever the case, please keep the insights and critiques coming! I want to consider everything I can possibly consider before drilling holes in the floor, buying gear, etc. If I'm limited on flow rate, I can at least maybe step my pump size down and save some money over the cost of the Iwaki MD-100.

Thanks!
- Aaron

 

[ellisz]

I had planned on buying a Panworld 200 or Sequence Barracuda to feed my tank. Both pumps supply more than my overflow. I had planned on splitting the feed off to feed my refugium and a frag tank. You could set some more stuff up and feed off the big pump

 

[Brisc0]

You could always add a hang on overflow that can handle it all and throttle it back with a gate valve to where you want it. This would make it so that you could at least cut out the bubbling factor down below a little. <still grasping at straws, but it wasnt said yet>

 

[amahler]

I think I'm screwed on a hang-on unit since this is an acrylic tank. It has a mostly closed top except for two decent sized rectangular openings cut in the top near the front. The canopy sits across the entire top as well.

It's nice in the sense that I get very little evaporation out of the top (the lights cover even this opening I described). Most of my evap, I suspect, comes from the right half of my wet/dry sump.

I just keep shootin'em' down, don't I? It's not intentional... just all part of the brainstorming process in a system riddled with challeneges.

Thanks!
- Aaron

 

[Brisc0]

I just keep shootin'em' down, don't I? It's not intentional... just all part of the brainstorming process in a system riddled with challeneges.

Wouldn't be fun any other way.

 

[amahler]

As I continue to think about this....

Imagine the pumps stopped. When I turn off the pump to do some maintenance now, my return flow to the tank obviously stops. I wait 30 seconds or so as the level in the tank drops below the outflow box "teeth" and the level of the overflow box drops below the top of the standpipe. This is the amount of extra headroom I have to allow in my sump and the reason I can't, obviously, top off the sump in a running state (I'd overflow it when the return flow to the tank stops).

When I turn the pump back on, the water level in my sump drops down a few inches to the normal running state as the inflow/outflow rate of the tank returns to its currently configured equilibrium.

In the running state, if I look into the overflow box (or through the front of the tank to the teeth in the overflow box), the water level for the spillover is very low. In other words, only the lowest centimeter or so of the inch or more high "teeth" are covered with spillover water. This, I assume, is based partly on the rate at which water is being returned TO the tank from the sump.

I already described earlier the fact that the standpipe going through the bulkhead in the bottom of the tank is definitely smaller than the actual bulkhead opening.

Does this indicate that I could, in fact, up my rate a good bit if I went to the full diameter of the outflow pipe and increased the pump size? What i'm saying is that the tank has what looks like a decent headroom on the draining rate if more of the height of those "teeth" are being used to drain a larger volume of the tank water at a faster rate. Again, it still depends on the maximum amount that can be drained through the hole in the bottom of the overflow box.

Am I making sense?

And again, how would one compute this maximum? It seems it's the max amount of water that gravity can drop through a tube the diameter of the overflow's bulkhead in the bottom.

I'm sure I'm just painfully describing the obvious here - but this is the first time I've had cause to reall think through the physics of this process.

Might this be the "standard" 600 GPH or so cited in an earlier post?

Thanks!
- Aaron

 

[Phyl]

A guy over on RC recently modified his mega flows. He drilled extra gap into the teeth so that more water would flow from his tank into the stand pipe. He has a dual return system and is pushing over 3000g an hour through it right now.

I'm saying where there's a will there's a way!

http://reefcentral.com/forums/showthread.php?s=&threadid=577452

 

[amahler]

Thanks, Phyl - that made for some rather interesting reading. I've got more questions and thoughts in my head now, though, dangit.

- Aaron

 

[Phyl]

I've got more questions and thoughts in my head now, though, dangit.

Better to think of these thoughts and question now than later, me thinks! All part and parcel to a well thought out plan.

 

[amahler]

Oh, I agree... I was just being droll about more questions coming up with every answer I find.

I'm not complaining - it's kind of a fun adventure and I definitely want to cover all the bases (which explains this thread and all the time I spent on 3D models). So I'm definitely not griping about your post, that's for sure... it brought up interesting other ways to consider my predicament.

Thanks!
- Aaron

 

[amahler]

I decided to send an email to the designer of my tank. He's been really helpful in the past and wrote back to me again rather quickly.

He said that my assumption that the bottleneck is the bulkhead in the bottom of the overflow was correct. It's 1.5" from what I can tell (and I think he agreed on that measurement).

He also said he recalls an Iwaki 40 at 4' of head being the biggest thing he's run on this configuration with success. I need to look that up again and see what those numbers are going to be and work from there.

In a nutshell, I might well be screwed on substantially increasing my GPH unless there are some more tricks. I suppose one could increase the size of the bulkhead and (ultimately) the teeth if that became the next bottleneck... but I don't think I'm wanting to take a drill to any part of this tank.

I've got more research to do to confirm all of this and, of course, I'm still eager for more input as others consider the dilemma.

All of this poking around has gotten me to wondering if I'm getting maximum flow out of what I already have and whether the drain could be less noisy than it is now. I'm planning a Durson standpipe ultimately... but even before that, I'm not certain things are flowing optimally. I might take some photos in a bit and post them to see if others see any misconfiguration in the current setup.

Thanks!
- Aaron

 

[ellisz]

I opened up the teeth on my overflow but not to that extent. I did remove a couple of the teeth all together like he did though.

Do you already have the pump? Just get a smaller pump. I would think 1000 gph would be feasible. You can always throttle the pump back or build a PVC manifold and dump some water back into the sump. Still a lot of flow IMO.

 

[amahler]

I checked and his reference to an Iwaki 40 on this configuration with 4 feet of head is in the neighborhood of 720 GPH. If I apply my parameters to this (assuming they are accurate), achieving that range puts me around an Iwaki 70 model. I had previously been looking at an Iwaki 100.

The cost difference isn't so great that it might still be worth just getting the Iwaki 100 and throttling it back some. I suspect that would still give me some headroom to allow for errors in my calculations or other unforseen stuff (assuming I'm computing it to be too ideal and not the other way around).

Would it make sense to scale back toward the model 70 or just stick with the 100 throttled? You do the throttling with a valve on the outflow, correct?

Also - what degree of life in the reef world will I be able to support with this config? I'm FOWLR right now. I suspect I'd need to at least add some powerheads to create more turbulence since I don't have a -tremendous- amount from the current (or future) outflow.

This irks me, though, because I'd rather not have to add potential mechanical noise to the system when I'm working to push all that into the basement.

There are always compromises in this hobby... I'm not sure I'll be able to pull off all my reef dreams with this config. Not that I'm unhappy with the FOWLR system, but I really envy all the reef systems I see with the gorgeous corrals and other more delicate creatures.

- Aaron