Indexing valves vs. multi valve sprinkler timers

[Daniel E Murphy]

There have been some questions lately regarding this.  i was hoping to get some feedback on these here.  I personally have an orbit lawn sprinkler timer wich is expandable up to 4 hoses.  I have it adapted to 1/2 flexible tubin on both sides.  It takes a battery.  Should I have gone the indexing valve route? 

[TCLynx]

I've added a discussion about indexing valves over on the TCLynx group as there were lots of comments building up about them. TCLynx Indexing valve discussion

As to the orbit sprinkler timer. I don't know the particular model you have there, nor what it's made out of.
Beware that brass or any other metal is likely to have issues in aquaponics and could also be bad for the fish.
Also, many of those sprinkler timers usually also require a certain amount of minimum pressure to operate properly.
And clogging of those hose timers might be an issue too.

Once you answer those concerns to your satisfaction, the next things to look at will be...

How many cycles per day will that timer do? Will that be enough water circulation/filtration for your fish?
What is the flow through on the sprinkler timer? Is that enough to flood your grow beds in a reasonable time?

Your last question will require me to ask some questions of you. How big is your pump and what is your system layout?
I am currently running my 300 gallon system with a 1 1/4" gravity modified indexing valve using a 50 watt pump that can flood my 100 gallon grow beds (one at a time) at 3 foot head in five minutes and they drain in about twenty minutes. I would definitely not recommend a smaller pump for use with an indexing valve. The particular pump I'm using is very efficient and I'm upsizing the plumbing between the pump and the valve as well. If you are running a smaller pump or are pumping up very high or using small plumbing, then I would probably not recommend the indexing valve to you.

To get enough flow and pressure to properly engage a 1 1/4" indexing valve I would suggest a pump that can provide at least 1500 gallons per hour at the height the valve is installed and is also able to pump at least 13 feet above the height the valve is installed. So if you had a pump that could produce 1600 gallons at two feet and it's max head was 15 feet then that pump should be able to operate the 1 1/4" indexing valve installed 2 feet above the water level no problem. This is my suggestion for the regular Aquaponics indexing valve set up for any outlet configuration of the 1 1/4" valve. I have been able to run on smaller pumps with the 4 way valve and of course with the gravity modifications but I want to make sure not to recommend smaller pumps unless I ensure the particular set up will still work reliably for a system.

[Daniel E Murphy]

That's good to know about brass and metals. Well this thing is programmable but not enough at only one interval daily... Owell back to the store.

TCLynx said:

I've added a discussion about indexing valves over on the TCLynx group as there were lots of comments building up about them. TCLynx Indexing valve discussion

As to the orbit sprinkler timer. I don't know the particular model you have there, nor what it's made out of.
Beware that brass or any other metal is likely to have issues in aquaponics and could also be bad for the fish.
Also, many of those sprinkler timers usually also require a certain amount of minimum pressure to operate properly.
And clogging of those hose timers might be an issue too.

Once you answer those concerns to your satisfaction, the next things to look at will be...

How many cycles per day will that timer do? Will that be enough water circulation/filtration for your fish?
What is the flow through on the sprinkler timer? Is that enough to flood your grow beds in a reasonable time?

Your last question will require me to ask some questions of you. How big is your pump and what is your system layout?
I am currently running my 300 gallon system with a 1 1/4" gravity modified indexing valve using a 50 watt pump that can flood my 100 gallon grow beds (one at a time) at 3 foot head in five minutes and they drain in about twenty minutes. I would definitely not recommend a smaller pump for use with an indexing valve. The particular pump I'm using is very efficient and I'm upsizing the plumbing between the pump and the valve as well. If you are running a smaller pump or are pumping up very high or using small plumbing, then I would probably not recommend the indexing valve to you.

To get enough flow and pressure to properly engage a 1 1/4" indexing valve I would suggest a pump that can provide at least 1500 gallons per hour at the height the valve is installed and is also able to pump at least 13 feet above the height the valve is installed. So if you had a pump that could produce 1600 gallons at two feet and it's max head was 15 feet then that pump should be able to operate the 1 1/4" indexing valve installed 2 feet above the water level no problem. This is my suggestion for the regular Aquaponics indexing valve set up for any outlet configuration of the 1 1/4" valve. I have been able to run on smaller pumps with the 4 way valve and of course with the gravity modifications but I want to make sure not to recommend smaller pumps unless I ensure the particular set up will still work reliably for a system.