New River-Tank Project.

[LES..]

Sweet design Martin, Is this the mystery project talked about previously or is that still to come?

Now lots of questions, as I have been thinking a lot about similar issues with concealing pumps and ensuring the fish will not get shredded by them although obviously from a much smaller single tank perspective ;-)
First off i have been planning to use the same strategy of a polycarbonate screen to separate the fish from the pump intakes so i'm very glad to see that part of my scheme backed up with similar thoughts from the river tank expert!

First question, to me it looks like you are sacrificing extra tank space where pump D is positioned, I assume this is to allow space to remove this pump for maintenance?

The return point of pump C looks like it would create a lot of turbulence around the false bottom of the tank A, had you considered converting this to a spray bar directly into the fish side of tank A? I believe that tank A will "only" have a flow equivalent to that provided by pump D in your current scheme, placing the return from pump C on the fish side would add to that flow.

I would also be concerned by water flowing back through the mesh above pump D. Would this be needed if pump C's return point is moved?

Do you need the lower tank segmented with the false bottom? All this seems to do is create a bypass to Pump C as you are suggesting that Pump I will be rated at an equivalent 1500gph it looks to me like you would get the same flow through the lower tank without Pump I if there was no false bottom.

Do you have any numbers on the wattage of the pumps and how much they will heat the water?
How will the lower tank be lit?

I'm sure you can see where i'm going with these questions, there is a significant risk that the conditions will become too hot for temperate fish if you don't have thermal management in mind.

I'd love to have the chance to play around with a tanks this size. Please keep us updated on your progress :-)

[Mad Duff]

Very nice design Martin, way over my head but nice nonetheless

[Martin Thoene]

Right....roll up your sleeves

No, this is not the secret project. I have shelved that idea because of aesthetic and logistic reasons, but now you've seen this design I will reveal the other idea because you may understand it better.

The concept comes from this:

http://www.endlesspools.com/whatis/what_work.html

As I know of no submersible small motor that can drive a fan I came up with this idea....projected to use the cooling fan from a car....probably around 10 - 12 inches in diameter.



Mount it on a stainless-steel shaft running in nylon bearings. Drive needs to be a speed adjustable motor designed for continuous running....ceiling fan motor. Gear reduction is by V-belt pulley diameter and could be adjusted if needed. I can get all sorts of diameter pulleys from Canadian Tire.

The fan sits in a duct mounted in a false floor, so water comes under the fish part and is moved up above the false floor by the fan, then goes into the tank via the mesh end wall. Out the other end though another and back under the floor.



I'm concerned about its aesthetics. The fan motor needs to be mounted fairly high externally. As you can see there's nothing to heat the water. I think potentially it could move a huge volume of water with no flow concentration like you get with a powerhead or conventional pump.
Also, I reckon that you lose at least 14" of fish space because of the reasonably large diameter fan.

Right....back to the other design. Let's see if I can answer some of your Q's.

First question, to me it looks like you are sacrificing extra tank space where pump D is positioned, I assume this is to allow space to remove this pump for maintenance?

As I stated, this is a not to scale concept to try and illustrate the idea. I will need to get the pumps and work out the packaging to maximize the fish part before I give the builder prescise dimension drawings.

The return point of pump C looks like it would create a lot of turbulence around the false bottom of the tank A, had you considered converting this to a spray bar directly into the fish side of tank A?

The guy that will probably build these tanks has 4" diameter supply pipes pumping 6000 GPH into his enormous Marine inverts holding tanks. Again, my drawing is not final. He has in one tank a T-piece that splits the incoming water into 2 spraybars. Each has 1/4" holes along its length to spread the incoming water. One big honkin' spraybar!
Yes, it could be ducted into the fish part fairly easily. With T's in a long pipe you could feed back through the right wall with bulkhead fittings that have strainers fitted. Fish could not then swim "upstream" in the return pipe. 2 or 3 bulkhead fittings would work nicely. It will still need the bleed-off hole J to act as a back-syphon break in event of power failure of pump C.

That return pipe is shown going up the right end for clarity. It would probably go up the back in reality.

I believe that tank A will "only" have a flow equivalent to that provided by pump D in your current scheme, placing the return from pump C on the fish side would add to that flow.

Good point, but it is 2600 GPH!

I would also be concerned by water flowing back through the mesh above pump D. Would this be needed if pump C's return point is moved?

I think that it's a good idea for equalizing water pressures each side of the wall. Again it could be a strainer-equipped bulkhead fitting. It's a fail-safe in the unlikely event of the left-end wall (E) blocking. Mind you, wall E does not have to be the full height of the tank, so water could flow over it in an emergency, but fish might go over too and be irretrievable from under the false floor. A top mounted strainer, normarlly emersed would solve that.
Before this ever has fish in it I will carry out worse case scenario testing. Block E with a sheet of plastic, see what happens I live in a rented penthouse apartment. There's a few people below me who will be pissed off if I screw up

Do you need the lower tank segmented with the false bottom? All this seems to do is create a bypass to Pump C as you are suggesting that Pump I will be rated at an equivalent 1500gph it looks to me like you would get the same flow through the lower tank without Pump I if there was no false bottom.

Yeah....you have a good point there. It would save me some bucks and it removes one heat-source. I could just have the mesh end walls to isolate fish from the pumps and filter box.
One disadsvantage of doing away with it though would be in the event of a problem with pump C. If C fails, water sharing stops and A's water back-syphons into B until the hole J breaks the syphon. At this point pumps D and I both being there mean that A and B become stand-alone River-Tanks and maintain water movement.
Of course, if all power fails it's a moot point.

Do you have any numbers on the wattage of the pumps and how much they will heat the water?

Seio 2600 is 52 watts, the 1500 is 26 watts. They claim these have low heat transmission, but relative to what? No figures are quoted.

How will the lower tank be lit?

I said somewhere above by flourescents mounted tight up under the upper tank.

I'm sure you can see where i'm going with these questions, there is a significant risk that the conditions will become too hot for temperate fish if you don't have thermal management in mind.

Yeah....as ever it's a concern. One reason for the ducted fan idea. One way I can help things is remove pump C from the tank. Have the builder drill the right end panel of B for a bulkhead fitting and feed directly into a non submersible pump. This is quite standard practice. A tap between pump and tank would allow pump servicing without tank B emptying. Being external means some of its heat can distribute to the atmosphere. Last summer, I purchased small cooling fans which helped immensely with the heat problems. I can use one to blow air over an external pump without the increased evapouration that blowing across the water-surface did.

Plus next Summer I'm investing in an air-conditioner. My apartment has no AC and gets kinda warm. Heating is a bit OTT here too in the Winter and not in-apartment regulated. Right now beside me my 65 gallon R/T sits at 80.5 degrees. No heaters.

It's -7 outside and I'm in shorts and T-shirt!

Martin.

[chris1932]

I really like this idea. I have a small stainless prop I would be willing to donate to the project.

[Martin Thoene]

Why don't you try it yourself Chris? I was being secretive before, but now I've decided to stay a bit more conventional someone else is welcome to give it a whirl.

Throw some street-rodder engineering at it. I'm sure with your workshop you're far better equipped to actually construct it than I am. If it works, slap a Moon sticker on the tank

(Martin and chris know what we're talking about)

Martin.

[chris1932]

Did you have a chance to look at the overflow diagram that topline posted? And its funny that you suggested that because after I read your post I went out to the garage and took an inventory of parts.

Old tripple winding fan motor
1/8" Stainless shaft
1/8" bore locking colars left over from dual quad linkage
8" ish Lightnin mixer prop

Looks like its time to fire up the phase changer and give the old Bridgeport a workout!

[Martin Thoene]

See...toldya! I know what most rodder's garages look like. Alladin's Cave.

Never throw anything away or you'll need it next week

Martin.

[LES..]

Thanks for the follow up Martin, it is much appreciated.

Your endless river plan looks like it would be well worth the effort in a large tank, alas that is way beyond my means at the moment but i will be filing that away for future reference.

Your point about overflow conditions is well made, I have no way of knowing just how fine your mosquito netting is but i can appreciate that it could clog easily if it is too fine. For my scheme i have opted to use a large foam sheet, usually used in pond filters, this will need supporting with a large opening grid. I suspect this will look significantly less pleasing than a thin mesh sheet but it will be removable so i can rinse it if need be.

It tickled me equating a 2600gph pump with the word "only" ;-) I'm sure you could fit 2 along that 18" wall! If you did that using a pair of Seio Super flow 1500 you would get a 3000gph flow for the same power load of your single Seio Super Flow 2600. Add in a more balanced flow of water across the tank and it may well be worth considering.

I followed the links you posted for your sump return *ouch* 140 watts power consumption, that's a a big one. I can well see the attraction of moving that out of the water.

You give a good reason for sticking with the extra circulation pump in the lower tank, I'm going to follow up with an extra question though ;-) Is there an advantage in having the flow by-pass the filter media? I appreciate that you will probably add a HOB filter to each tank but you would lose a fair bit of bio-filtration should pump C fail. You mention by-pass holes should that filter clog but a simple corner weir would take care of that and allow for the lower tank to filter independently of the top one.

Fantastic stuff :-)

[Martin Thoene]

I said that I would probably go with an AC110 HOB on each tank...1000gpH of sponge filtration....overkill anyone?


The primary purpose of the bioballs in the top tank is low-restriction noise reduction. These weir systems can be a bit noisey and this will be in my lounge. I figured the bioballs would break up the flow a bit and maybe quiet it? Experimentation.....

The lower filter idea with a ceramic media is a bonus idea I thought of. Could do away with it, flip the flow by putting the Seio 1500 on the left end wall so that its flow, plus the top tank overflow come in on the same end. Might be more efficient.

I want a straight dump into the tank for no restriction, no risk of backup. That precludes ducting it in through the left wall with bulkhead fittings with strainers. I figure dump it in a left-end chamber and let it take the path of least resistance to the Pump C. Water will always do that of course, which helps, so it can go through a mesh-guarded vent window in tank B or under its floor.

I'm unclear on exactly what you are talking about with a corner weir. If you could sketch it, I work better with visuals

Martin.

[crazy loaches]

Martin, the quitest and highest flowing method for the overflow is a durso style standpipe: http://www.dursostandpipes.com/ It allows the water to build up to a higher level - not splashing down over the baffle to the bottom of the overflow chamber - more like a couple inch fall I beleive. And it has a submerged intake so what noise there is is muffled. You loose what bit of filtration the bio balls may offer though. I see the advantage of your false bottoms now, being able to run both tanks independantly if needed. Not sure if thats something that would ever come in to play though. Plus you can have a higher flow rate without worrying about the limits of the overflow and return. You probably could do a single tank setup first with the false bottom without needing the complexity of the overflow and sump tank.

[Martin Thoene]

Ooh! .........I like that! Thanks crazyloaches. That's a very neat idea and I see how it works. You could actually still fill the chamber with bioballs. It just wouldn't necessarily have full flow-through of the media, but there would still be bacteria growing surfaces.

Martin.

[crazy loaches]

Ahh yes, I forgot about that. The overflow chamber then becomes a mini 'refugium'. The only tricky part is drilling the right size hole in the top to allow a controlled amount of air to pass - then it becomes self priming, and minimizes lots of air sucking in causing the flushing noise many overflows have. But its not really hard at all.

[chefkeith]

Martin, Thanks for sharing your ideas. I've been wondering for along time what your Eureka moment was. It is far different than what I imagined. It's definately hard-core. Can't wait to see it built.

Here's the link to your old thread on the subject for those that haven't seen it yet-
http://forums.loaches.com/viewtopic.php?t=2663