outdoor/greenhouse PPK

[Speed of green]

I need some advice on ideal solution temp for a PPK, I have a greenhouse that i would like to try a PPK in.

has anyone tried this? and ideas or thoughts as to why it would or wouldn't work?

 

[Speed of green]

My idea for the design is a large gutter made of some beefy sheet metal, probably 14GA because it will have to support the weight of all the plants, i plan to bury this gutter so that its almost flush with the ground and completely level. I planned to bury the gutter so that the solution temperature would remain more constant, and give me more head room for the plants.

This metal gutter will be 11" square with a 3" opening in the top for the PPK tailpiece.



The metal gutter will be 20' long to fit inside my greenhouse thats 24' long.

In the center of the gutter will house a float valve that will draw from a 50 gal elevated reservoir, at each plant site there will be a pump to feel a watering halo.

This is a drawing of a cross section of the metal gutter.

This is a drawing of the entire setup, i realize these pictures are pretty shitty, sorry about that.

 

[queequeg152]

how do you plan on fabricating such a gutter.

the profile you show in that pic is bascially impossible to build on a conventional sheet metal break.

also you are going to be very hard up to find any sheet metal shop with a 10' break let alone a 20' brake. so you need to include couplings and waterproofing details into your design.

imo your starting premise is faulty from the get go... instead of steel supporting the entire weight, you should look at digging troughs and waterproofing them with a membrane, then spanning the gap with wood members or steel members.

no clue what ppk is... but im guessing its something "passive" wicking or what ever.

if you are still using containers for the bulk of the root mass, then you could even consider burying a large diameter pvc pipe. just need a router and jig to cut a large square slot along its length.

 

[Speed of green]

I am a sheet metal contractor, and a have a 10' pan brake. The top opening will be hemmed instead of the 90, and for joining the 10' sections I will notch and taper the two pieces so they slide together nice and tight. I'll seal the joint and endcaps with geocel and pop rivets.

in my mind sheet metal is the easiest material to construct this from, the pvc pipe would be great but I think balancing a large plant and a 50+lb pot would stress the plastic.

 

[queequeg152]

well it certainly would be the easiest/fastest way, and hell if you have the tools... the question is why WOULDN'T you make it from steel lol.

so you are saying the top part would be a flattened hem? so you would make those two hems , then fold it on the finger brake? that makes sense to me.

regarding the PVC.... imagine a pvc pipe canoe, thats what i meant. you would basically cut off the top 1/3rd of the pipe along the entire length, or at each individual site.

i still dont see why you would need the weight of the plants to be handled by the steel though.

if you are going to bury them, then why not just let the plants sit on the earth? then you could use cheap 24 gauge or maby 20 gauge if you want to be able to dig the up and move them around.

since you have the equipment... you could even make sliding covers or caps. the caps would slide under the container, but not interfere with the roots. spray a little PTFE dry film coating spray and you are good to go.

 

[Tbonegrower]

This sounds intense!

 

[Speed of green]

So after playing with the idea a little i decided to just build a series of level platforms for the ppk sites and go the traditional route of 3.5gal buckets instead of the sheet metal/gutter idea.

My answer for the high temperatures in the nutrient solution is a hose that links from the last ppk plant site directly back to the control reservoir, there will be a small pump in-line that will slowly recirculate the nutrient solution. inside the control bucket will also be a chiller.

This will be mirrored on the ppk pump bucket side as well.

Im trying to size a reservoir for my volume tank. i want to get at least 4-5 days in between mixing batches.

this will be a 17 site system with 3.5gal buckets and 7gal feed pans, plants are going to be tree style, im curious how much these things will drink.

i have a 5 plant ppk indoors that is drinking about 20gal/day plants are about 4' in diameter.

does anyone else have input on daily water consumption in your ppk system?