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Horizontal Tube bed

Well my wife convinced me to add an additional bed so she can be part of the fun. First of all she is going to plant sweet grass (she is native american and they use it for ceremonies and basket making). I have an 8 foot 4x4 pvc fence post tube we are going to cut open and make it a window box unit. Seeing as it is only 4" deep, which for this plant is more than enough what would you all suggest for a drain system?

Thanks

John

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Replies to This Discussion

Permalink Reply by John Cubit on October 19, 2012 at 3:08pm

Still stuck on this. It seems that a bell siphon would be impractical since the drain would be less that 3" and the total out the bottom of the bed would need to be less that 4" or else I would need to add a sump which in the kitchen would also be impractical.

Anyone have any thoughts on what to use?

Permalink Reply by John Cubit on October 21, 2012 at 2:51pm

Ok so this is really starting to suck...or not. I tried a bell siphon and the bell floats away. What the heck! My other bed is fine. So I tried a pvc loop siphon, starts but never stops and never lowers the water level. I think it may be time to take a break and eat.

Permalink Reply by Mark on October 21, 2012 at 3:12pm

Could you use a timer on the pump for a flood and drain setup. The system would always be draining slowly the pump would fill the system and then stop. You would have to put a safety overflow tube in the system incase the drain tube got clogged, it would work like an overflow in a bathroom sink.

Permalink Reply by John Cubit on October 21, 2012 at 6:52pm

I am thinking about that. problem is I am sharing a single pump to a 10 gallon bed and the horizontal is a 5 gallon bed. I think part of the problem may be the flow in. I put a waste valve on the in to the horizontal tube but the flow is so slow it may hinder the drain. The main bed is running great so I didn't want to put a timer on it and possibly effect the good grow bed. I might swap the bell for a loop siphon using a tube instead of the pvc. Def. wanna add an overflow. That is why I left the gaps at either end so that I could have the drain on one end and an overflow on the other.

Has anyone else ever used the pvc fence post like this before?

Mark said:

Could you use a timer on the pump for a flood and drain setup. The system would always be draining slowly the pump would fill the system and then stop. You would have to put a safety overflow tube in the system incase the drain tube got clogged, it would work like an overflow in a bathroom sink.

Permalink Reply by John Cubit on October 22, 2012 at 11:20am

So I made a longer drop on the drain and the bell stopped floating away. Problem now it is not consistently draining. I have to lift the bell to get it to start and it will empty fully, then gets stuck of if I stop the water and empty, then begin to fill again it will get to the point of the top of the drain and get stuck at that level. I had it working for a bit yesterday and I am thinking this is all because of the flow.

Next is to replace that waste valve which restricts the flow way to much. I am still not going to rule out a timer but while the other bed has plants growing I am still waiting for many to take root before I lower the water level.

Permalink Reply by Mark on October 22, 2012 at 12:20pm

Yes I agree you should increase the flow, Do you have an elbow after the siphon this will help the siphon start, you could also reduce the size of the siphon pipe, if you are using 1/2" PVC for the siphon try an adapter and use a 1/2"CPVC it is a little smaller. Also make sure you have plenty of holes in your gravel guard. I am using 1/2"CPVC for my smaller bell siphon , and I had to add the elbows to make it work right. Good luck Mark

Permalink Reply by John Cubit on October 22, 2012 at 7:55pm

Yes Mark, I have an elbow after the siphon as well as 1/2" cpvc feeding into 3/4" drain in the siphon. I also added a breather line to the bell to break the siphon but that really does nothing.

Thanks for your ideas.

Permalink Reply by Mark on October 23, 2012 at 7:33am

Can you make the siphon longer under the box? I think this is your problem. As the water leaves the box the longer tube holds more water the weight of the water falling helps create the low pressure above. My siphon from the top to the first elbow is about 6" and then continues down another 4". If you can, lengthen the pipe in picture #3 by about 4" or more. Mark.

Permalink Reply by John Cubit on October 23, 2012 at 2:01pm

I am going to have to see what parts I have left. If I drop the drain lower I will need to add a "U" to get back to the height and drop to get the water to the tank. Of course this morning my wife said do you need a bigger tank...I think she is totally falling for aquaponics.

I did pick up two new ball valves so I am going to add those first before I do the drain. Note to anyone else reading, do not buy a CPVC Waste valve, it will stop nutrients from making it to the tank and will never allow for the correct flow. Keep you all posted.

Permalink Reply by John Cubit on October 24, 2012 at 2:02pm

Changed out the waste valve with a ball valve for each bed with a master flow valve. The large bed is now flood and drain with less water flow than needed before, and the tube bed is now showing it's own problems.

I dropped the drain down another 4" but needed to add 2 more 90's to get back to the height that would allow to drain back to tank, now I am back to the original problem of the floating bell. I assume that air trapped in the "U" is causing the floating. Also I noticed that probably due to the length and the density of the Hydroton that the end with the fill tube fills faster than the drain side. I am almost tempted to use it as a constant fill bed with 50% fill of water in it

Permalink Reply by John Cubit on October 25, 2012 at 10:11am

So now I have removed the U and put the longest down pipe I could (4") and still allowing gravity to get the water back to the fish tank. Got siphon to fire but now it won't stop. Guess I am still at square 1. I am going to see about raising the bed another 2" and see if a 6" pipe helps. I have played with the flow hoping to avoid raising the bed but it seems that with such a small bell (4") may actually be the problem. I did add a breather tube to help break the siphon but that did nothing except gurgle all the time.

If any of you experts out there have any suggestions please chime in. Again this is a 4"x4"x6' pvc fence post cover that I have cut open to make a grow bed for sweet grass. I know normally folks would cut holes in it and place baskets in but that would not be practical for grass that starts from seed to form new growth off the rhizomes. So it needs to spread out and a basket would hinder that.

Permalink Reply by loki on October 25, 2012 at 11:59am

some thing you might want to think about is drilling a like a 3in hole where your current drain is. take a 3in pipe coupler and cut a small section off like 1/2in or 3/4in, this will be glued to the end of a small 3in pipe sectionand then glued to your grow box the other part of the coupler will conect to the 3in pipe from the out side to seal the hole. the ad a small section of 3in to the other end with a reducer to what your stand pipe and your fish tank return is. then run a bell siphion on the inside of the 3 inch pipe! the reducer may need to be threaded to get your drain and stand pipe to share the same space!

the lip on the inside of the grow bed should hold back the water long enough to brake the siphion and by having a larger volume of h2o going through the stand pipe should help start a siphion!

i am not a expert nor do i have a AP sysetm but i think that by having a more natural sized bell siphion it might be more tune able!

you could also just pull your bell out and just have a constant flood/constant drain or reduce the water flow in to be slightly smaller then the flow out!