Pumping into the bottom of the fish tank

[Jason Finn]

Has anyone ever tried to pump water into the bottom of their fish tank in order to cut down on the height they have to pump?

I was thinking of feeding my pump into the bottom of an IBC tote and pumping the water into an air pocket (upside-down bucket) at the bottom of the tank. This would reduce pumping height and in turn reduce the wattage needed and maximize the gallons per hour which it is always scary how fast GPH decreases with height.

Anyone think this would work?

I am assuming that fitting the pump's tube into the bottom of the IBC pipe without leaks would be a challenge, so anyone have thoughts on fitting that also?

[Keith Rowan]

that's not going to reduce the head per se..how would you maintain a bucket of air? the water will just fill the pocket.. you'll still need the initial power to pump above the surface of the water you are pumping from, but once you turn off the pump in the situation you describe, it just becomes a siphon (or water bridge)..

[David - WI]

It wouldn't matter anyway... the air pressure in the bucket would be the same as the pressure of the water around it; no gain.

[Jason Finn]

I think you are probably right David, that the air pressure may be the same as the water at the bottom of the tank. Keith also brought up a good point about creating a siphon and in my theoretical system this would then pump all the water out of the tank. I would have to make the air pocket huge in order to compensate for this and it would probably defeat the purpose (haha).

The water however would not fill up the air pocket because the air must move up and its trapped. I did a mini experiment with a five gallon bucket filled with water, a cup turned upside down and held at the bottom, and a soda bottle (cap off) with a 1/4 inch tube stuck in the bottom and held in the air. I put the other end of the tube in the air pocket and someone else held the bottle and it worked just as expected. Gravity is the force in this experiment but what I really want to do is test it with a pump doing the force instead and from below.

The only way to test what I want to do with this idea would be to scale the experiment up and use a pond pump which I do have. I ordered 10 IBC totes a little while ago to be delivered to my house (it will take a few weeks) or so and when they come in I will be testing this with a bucket, a tote, a sump tote, and a pond pump before I set up my system. In the mean time I welcome everyone to criticize this concept so I don't end up wasting my time (haha). 

[David - WI]

But... we both told you that you are wasting your time.  .

The "pumping height" is the difference in height between the water surface in the tank that you're pumping FROM and the water surface of the tank you're pumping TO... it doesn't matter where the inlet or outlet or pump or pipes go.

And it doesn't matter if you throw a bucket in there or not.

[Harold Sukhbir]

Hi Jason,

The pump will have to do the same amount of work to pump up to desired height or through the base rising to the desired height. So, there won't be any difference in your energy use or flowrate. But it shows you're a thinker!, which is exactly what you need for AP. I'm not familiar with the fitting at the IBC base, may be someone could chime in here. Just get a PVC male adapter for the hole in base and one or more reducer fittings to match your pump outlet size. 

[Vlad Jovanovic]

If your IBC is made by Schutz, Clawson, Fustiplast, your outlet is S75 (75mm) x 6 male buttress (coarse thread).

If your IBC is made by Sotralentz, Grief, Sonoco, Mamor, your outlet is S60 (60mm) x 6 male buttress (coarse thread).

If your IBC is made by Mauser (Hoover), your outlet is S80 (80mm) x 6 male buttress (coarse thread).

I've connected things to these in a number of different ways to a number of different sized hoses...depending on what I needed to accomplish.

This red cap pictured is one with a quick connect fitting... The threaded black piece in the foreground goes on the inside of the cap, and the orange (or green) piece just screws onto it. Use appropriate rubber washers and/or something like 3M E5200 Marine adhesive-sealant on the flange (of the black piece...between it and the IBC cap) so that you don't get leaks...You could also do the same with the white 1" male adapter (again, just use a washer or E5200 on the 1" adapters flange where it contacts the inside of the cap. AND make SURE that you use some type of threaded lock nut on the outside of the 1" male adapter between it and the IBC cap (obviously)...

You have to drill out whatever sized hole you need in the IBC cap. No biggie there...

I don't really think your idea will work in the way you hope it will, but hell...that shouldn't keep you from trying and seeing things for yourself

[Bill Bailey]

Not sure of exactly how your design is now BUT .....  The Info I received from a Michigan State University Dir/Dr. ... He said he would not take "any design seriously" that does NOT have Gravity driven water in it, or the ability to turn water 1.5 times a day.  I've run into so many people here that have literally spent $Millions in Aquaculture and have quit because they say it just DOESN'T WORK! One of these guys name is Tom and is 4 miles from me. He has 6 or 7 ponds and lakes that he raises Salmon in. Commercial Vertical Filters were having the media plug up, Pumps and Motors burning out, etc. I know Tom and I contacted him about an Aquaponics setup, he blew me off, said he had heard it all, he is 70, and it just doesn't work here, Salmon require VERY LOW Suspended Solids and cold water, which we have, and 1 Lbs of Pellets for every 1" the fish grows. So I asked him how much to buy his place ... He said around a $Million ... OUCH!  A Million Dollars for a place he says doesn't work???  But it IS hard to do ANYTHING with Gravity when all your ponds are at ground level.

In my tank DESIGN setup water is driven by a well point that is free flowing.  The well pushes the water up to a large tank over the other tanks.  As water is pumped out of fish tanks into DWC system the tank on top replaces it. We already have a 1.5 Acre Pond fed with Springs and a point driven that was stopped 16 inches before water came out Free Flowing so we know we have that set.

[Ki Pi]

Is anyone taking into account that if you pump water into the bottom of the fish tank that if your inlet to the tank is at the bottom of the tank the pump will have to contend with back pressure of all that weight of the water in the tank trying to force it's way back to the pump? Cute diagrams btw.