Backyard Aquaponics
A place to discuss aquaponics

Another teacher said to me the other day an interesting thing that i hadnt considered.

"Why use a timer on your pump? Why not instead put a 12v float switch on the top of the inside of a stand pipe syphon level with the internal pipe so when the grow bed is full, the float switch connected to a solinoid stops your pump?"

I thought its a great idea and one worthy of discussion. So topic is:

Specifically with Flood and Drain systems, what are methods of being able to flood the system, stop the pump, then drain the system and start the pump again... What are some innovative ways to do this.

There is the obvious timer on the pump, but talking to members has me to ask - what is the best timer for your system? And that obviously depends much on the size of your growbed and the time it takes to flood and then to drain... Some timers are not that sensitive...

With the teachers discussion above, my thought it what happens when the growbed is empty... how do you either 1) tell the pump to start pumping again, or 2) When the water level drains below the float switch, will the pump start up again which defeats the purpose...

What are your thoughts?

Are the 12v floats different from the 240v ones?

The floats I have in the monster and the sump turn the pump on when the water level is high and turn it off again when the level is low. I've been told you can also get them wired the other way around (turn off when the water is high and on when the water is low). I would think that if you were putting a float in the standpipe you would have the second type (off/high-on/low).

Would the standpipe diameter be large enough to fit the float and it's cable and allow its free movement?

The other thing though is you have 1 pump, but more then 1 stand pipe growbed and your stuffed as you need to keep the pump going till all the growbeds are filled.. hmmmm

Diameter might be ok, if you had a large pipe

Phro, i think he may have been talking about a really small level switch, they tend to operate vertically and only have a few cms between off and on. prbably more trouble than its worth.

Timers are the easy option if your flood time is 10+ minutes. otherwise go for the autosyphon

Before commenting I just want to get the idea right . Are you talking about standipes, or syphons??

If you could find a reasonable and reliable, high flow, low pressure solenoid valve... then it would work. Remember it has to be fail safe. For anyone running a 12 or 24 volt system including pumps it would be easier. Ideally would would want to to use actuated ball valves or butterfly valves instead of diaphragm style solenoids.

Best price these types of valves before contemplating using them, they can be rather expensive (or go looking fro 2nd hand ones)

I mean stand pipes... I thought they were called stand pipe syphons sorry...

I think a timer is the best option... the question is now... what sort of timer, and how to set it up?

Hi mcphro i use a clipsal tc32v1 i hour timer 15 amp and it will time down to 37 seconds on depends on your setup i only run my pump 3 min in the hour see my thread

actuated ball valves are quite expensive, most of the ones ive seen are either hydraulic or pnematicly powered

bunnings has plug in timers with 4x15minute intervals per hour for around the $25 mark

Yeah I bought the same sort from "B" and they were on sale for $10 for 2...

But you need more of the plastic tab thingies... they usually only come with 6 on/off tabs. I have had great success with the digital ones. You could piggy back them to get more on/off cycles.


Plus.... I agree the actuated ball valves are very expensive, however they are the ideal solution. I still have to talk to my uncle about getting hold of one to play with....

the problem i think will be having to have an air compressor to power them

tim, nah te ones we're talking about have 72 built in tab thingies (not removeable)