More About Indexing Valves

[TCLynx]

So I got some more questions about these indexing valve things so I figured I should go ahead and write a bit more about them. They may not be appropriate for every situation but they do have their place.

Want to sequence the flow of water into your grow beds to only flood one at a time? Want to avoid extra wiring and control electronics? Then consider an aquaponics indexing valve. All that is needed to operate this valve is a flow of water that starts and stops. If you are already running with a pump on a timer, then each time the pump stops then starts again, the water will be flowing to a different outlet. This is a way to add more grow beds without needing to expand fish tank or sump tank space.

Aquaponics Indexing valves!!!!!!

http://www.aquaponiclynx.com/aquaponicsHIW.swf

The valves come in three different sizes. 1", 1 1/4", 1 1/2" They also come in a few different bodies. 4 outlets, 6 outlets, 8 outlets (only in 1" though)
There are cams that can be installed in the valves to allow them to operate different numbers of outlets.
For example the 4 outlet body can be cammed to run 2, 3 or 4 outlets and one would simply cap off the unused outlets if any.

http://www.aquaponiclynx.com/aquaponicsBeds.swf


Now these valves are similar to irrigation indexing valves but with some modifications to make them work with aquaponics, there are also additional options we can provide for the aquaponics indexing valves that one can't get by purchasing the indexing valves at the big box stores.

There are minimum flow and pressure requirements to operate the different models of valves and I can assist in choosing the correct valve for a situation or recommending an appropriate pump size. Here is a link to a site with listings of dealers for different parts of the world.
http://www.aquaponiclynx.com/indexing-valve-dealer-map.htm

[TCLynx]

Aquaponics Indexing Valves Dealer Map

[TCLynx]

The list prices range from about $72-110 in the USA depending on the model, size and number of extra cams. Each dealer has a little leeway on price so I would advise contacting the dealer for your area.
Unfortunately the dealer map doesn't really make it clear who covers HI so let me know if you are interested and I'll put you in touch with some one who can take care of you.

[Chris Smith]

What is the price range of the valves?

[TCLynx]

The manufacturer recommends 1 minute of off time but it really only needs long enough for the water to drain out of the valve to allow it to move forward so this is dependent on the plumbing involved. I've done as short a 30 seconds where there is minimal plumbing to drain back.

[Chris Smith]

Thanks for the info. How short of an off interval does the valve need to advance?

[TCLynx]

No Siphons needed this way, it is more like timed flood and drain with standpipes. Only you flood just one bed at a time (or a group of beds if they are small.)

And they don't really all have to be the same size as long as the small ones drain freely enough that the extra water will simply flow down the stand pipe, it just causes extra aeration and circulation through the system.

Timers, it can be done with a simple (make sure it's a high quality one so it will last) mechanical 15 minute increment timer so the pump is on for 15 minutes and off for 15 minutes which will work fine as long as the pump is big enough to move the volume of your fish tank in 1/2 an hour.

On my 300 gallon system I'm using a home made repeat cycle timer I made and programed a picaxe chip for so it is running for 9 minutes and off for a minute. This way, once I get all 6 beds online, each bed will get flooded once per hour. Just gotta make sure they drain fast enough that the fish tank doesn't get too low yet they gotta drain slow enough that the pump is able to flood them in the 9 minute time frame.

I have another indexing valve that is fed by a pump which is on a float switch which has been working well too.

If you are going to use a timer, there isn't much point in using a siphon. Siphons are good for flooding and draining a bed that gets a constant inflow.

[Chris Smith]

What kind of timer do you use to turn off the pump when using an indexing valve? Do all the beds need to be the same size? I assume that the timer has to be set just right so that the bed does not continue after the siphon is triggered.

[Sahib Punjabi]

Great post :-)