Backyard Aquaponics
A place to discuss aquaponics

I have a 5500lt tank and 1700lt tank. They are about the same height. If I place an upside down u pipe to the 2 tanks, down to the bottom of each tank, and pump out of the large only, will the height drop equally in both tanks? I know nothing of physics obviously!

Help please.

Hmmm, my heading is wrong, should be equalizing heights!

Yes it will work provided the pipe is full of water. The concern is that if the pipe gets blocked or gets air into it somehow and the siphone stops working, then you will be stuffed.

yes, VB put it lightly.... If, what essentially is a siphon breaks, then you are in a lot of trouble. What you really need to do is feed a piece of air hose into the very top of the U-bend and glue it in place. Feed the other end down one of the tubes, and have is accessible so you can get to it very easily. What you will need to do to start the siphon is put both ends in the water and suck as hard as you can to get all the air out of the top of the U bend.

Then periodically, suck any air bubbles out of the top of the U-bend to ensure that there is no air.... IDEALLY get a piece of clear tubing for the top part of the U-bend, so you can see if the air is accumulating. Keep it covered, to stop algae growth. If you need a picture, let me know. It is mainly there for emergencies...

Keep in mind if the U-bends are deep then air bubbles will most likely not travel up the tube, however micro bubbles will accumulate over time.

vb, I have had no problems in getting air locks and had one connected to my 2 sump tanks for over 6 months (just make sure all joins are air tight - like GLUED!!!).

I used 40mm piping, had about a 20mm gap between the base and the pipe end, then wrapped some gutter guard around the the pipe extending it to the base of the tanks...this kept the fish from swimming into the pipe and going to different tanks (well - so the theory went )

Yeah TT - works fine, just match the pipe size to the pump flow so that there is little lag time in the water flowing from either tank and make sure that the water level doesn't drop below either pipe end. (if one siphon proves to be too slow, just add another)

Now that is teamwork, I guess I scraped in just a few seconds before you Ell.

Sorry Tim, posted at the same time - really have not had a problem with air locks, I think that any air that does get in the pipe gets dragged out on the next flow cycle.

My way of filling the pipe with water
1) submerge the siphon contraption in one of the tanks and fill the pipe with water
2) while the siphon is still submerged, wrap 2 pre-cut pieces of plastic (I just used Woolies specials carry bags) over the pipe ends...this holds the water in the pipe
3) Holding the plastic onto the pipe ends with both hands - invert the siphon then put either end into each tank
4) remove the plastic sheets

I can take some pics to make it clearer if you like tomorrow

Thanks very much team. I use 40mm pressure pipe to pump out of the tank so it seems this would be ok to use as the u shaped tank connector. Thanks for the tip on the gutter guard Les.
I glue EVERYTHING, which in this case at least, will be a good thing.

Now who is gunna help me sneak that big shiny milk vat into my garage?

i would, but the overwhelming urge to club you over the head and make off with it might be too strong

Look - if you have space problems with it, I can find a nice covered area that you would think was specially made for it

Just on the milk vat.

Would it be possible to pump heated water thru those coils in between the stainless walls? This water would be in a closed system and would not come into contact with the fish system. I am getting very excited about growing heat loving fish out over winter, if I can heat the water economically.

A slow fire under it would work...

OK. some problems.
First, if you pump too fast, tank 1 will drain empty before tank 2 can equalise.
Second, airlocks are a real bugger.

To limit airlocks, get a foot valve, which is a one way valve for the bottom of the pipe with a grille on it to limit fish getting caught.

To eliminate airlocks, join the pipes as you have suggested. then add a one way valve at the top, to which you join the pump.

This way, the pump will always suck the air out of the pipe, and the tanks will equalise. - this may play up if you plan on draining the tank. But if you're keeping fish in there it's going to be the safest technique.

TT, was waiting for you to ask!

first, check if the lines have any sort of restriction or metering device. from memory all the gear is external.

maybe just hook a hose up to it and see if you get reasonable flow through it.

if yes then we can talk

actually, hold that thought........................

might be able to hookup a refrigerant backyarder setup for you................best not to put water in there! use compressed air or your mouth

Something so simple - yet I had never thought of it

One thing that I am not sure of tho TT...you say water travelling in one direction from the large tank, which tank do the GBs empty back into - if it is going into the smaller tank, then the water will be flowing in one direction through the siphon pipes - this is fish tanks for your system yes???