Backyard Aquaponics
A place to discuss aquaponics

My first system, what I consider my "learning" system is taking shape.

I started with two 400L stand alone tanks with lots of air pumped in and rafts on top. This was to get some water cycling. I am almost done adding an 800L grow bed. Then I will convert the second FT to a sump tank.

I have not finalized some crucial details yet. Some of it depends on what I can find available (and what else I learn from this site.)

I will pump from the sump to the FT, gravity flow to the GB and siphon back to the sump. I may use a bell siphon and a continuous low volume pump or a higher volume pump on a timer with just a drain.

Which will use less power? When I am done I want to run this solar (I am a solar contractor.) Currently the air pump is running off a small trickle charger and a 750 watt inverter. With energy efficient pumps it should not take a lot of power, and I will shut everything off at night.

I would advise to keep at least the air pump running at night if you can manage the battery power. Dissolved oxygen can really be used up overnight since plants will take up oxygen and give off CO2 at night. If any algae is in the system, it will add to the problem and the fish don't stop metabolizing just because it is dark.

Otherwise sounds good.
as to what is more energy efficient, small pump and continuous operations or more powerful pump and timer. I suppose it depends on what pumps you have access too and the overall size of the operation. One tip, hook the pump up to larger plumbing than strictly needed and you may get more out of a smaller pump. The main point is you want to be able to pump at least the volume of your fish tank each hour. Pretty easy to figure out with a small pump running all the time. If you will use a timer and larger pump, you want to look of an energy efficient pump that can more at least the volume of your fish tank in whatever increment of an hour you will have the pump turned on. With such a system, you can probably manage with a relatively small pump even running on a timer. I expect you could probably manage overnight operation on such a small system with even a modest battery.

Things are up and running. I had quite a time getting the bell siphon to work, all the various pieces effect something else.
I had no trouble getting the siphon to start, my problem was getting it to stop. At first I had a tube to break the siphon that was too small in diameter.
The real problem is balancing the flow coming into the GB. Just before the siphon kicks in there is a small trickle that develops. If the inflow is too slow, this will prevent the siphon from turning on.

On the other hand, when the GB is nearing empty the flow rate through the siphon slows, almost stops, then starts. Currently it takes about 2 minutes in this slow start/stop condition before the siphon breaks. Several things seem to effect this: the flow rate from the FT to the GB has to be slow enough, there is a lot of water in the GB that takes time to filter through the media to the siphon, the amount of rise at the end of the outflow tube.

I need to add a timer to shut the water pump off at night. There is a small air pump that will run all the time.

It works quite well, but its not that easy to get it all balanced! 17 minutes to fill, 5 minutes to drain.

Things are certainly moving along in the right direction Jerry...