zem
Well-Known Member
due to the request of some fellow growers, i will post a brief hopefully understandable DIY method of how i make my grow trays. this has come after years of experimenting and trying different things and i find this to be the best and the cheapest. the key is to find the black geomembrane, it is black nylon specially intended to make huge deep outdoor ponds. i found it in greenhouse supply companies who sell all kinds of greenhouse plastics for tents and so.
list of things you need:
-wood sheets, any thickness that can be screwed into a shape of a box and be sturdy, 1/2"+
-L shaped aluminium bars
-2 drains
-hoses screws and fittings
-geomembrane
-a small piece of vineyl or rubber sheet(optional) 5"x5" would do
it's very straightforward, shape the wood like a box and drill holes where you intend to make the drain and overflow. the holes should be bigger than the drains.
shape the geomembrane inside the box and screw it to the walls with the aluminium bars.
now cut holes in the nylon where you want to place the drains. i chose to reinforce it using the vineyl sheet. you can however cut several pieces of the geomembrane sheet and use them for this purpose. just make the same size drain hole in each piece and place them under the first nylon layer so that it comes in between it and the wood in bottom of the box. sorry i got no pics for this...
now all you have to do is screw the drains to the holes, you dont need to tighten too much, it becomes waterproof as soon as you start tightening. 3rd pic you can see the overflow hole with the hose. all i have to do is raise it to desired level or raise it above table if i want to switch DWC. i can fill this table with rocks and use it flood/drain or i can fill it with water and place a lid with holes and use it DWC. the lid just lays perfectly on the L shaped aluminium bars. pics tell the whole story. i use PVC boards with some insulation for the lids.
the nylon is guaranteed for 3 years in outdoor sunlight conditions and under high pressure of deep ponds so i guess i will grow old before i have to replace it indoors lightproof shallow conditions lol and i have a roll of it for cheap. my tables are about a foot deep.
enjoy!
list of things you need:
-wood sheets, any thickness that can be screwed into a shape of a box and be sturdy, 1/2"+
-L shaped aluminium bars
-2 drains
-hoses screws and fittings
-geomembrane
-a small piece of vineyl or rubber sheet(optional) 5"x5" would do
it's very straightforward, shape the wood like a box and drill holes where you intend to make the drain and overflow. the holes should be bigger than the drains.
shape the geomembrane inside the box and screw it to the walls with the aluminium bars.
now cut holes in the nylon where you want to place the drains. i chose to reinforce it using the vineyl sheet. you can however cut several pieces of the geomembrane sheet and use them for this purpose. just make the same size drain hole in each piece and place them under the first nylon layer so that it comes in between it and the wood in bottom of the box. sorry i got no pics for this...
now all you have to do is screw the drains to the holes, you dont need to tighten too much, it becomes waterproof as soon as you start tightening. 3rd pic you can see the overflow hole with the hose. all i have to do is raise it to desired level or raise it above table if i want to switch DWC. i can fill this table with rocks and use it flood/drain or i can fill it with water and place a lid with holes and use it DWC. the lid just lays perfectly on the L shaped aluminium bars. pics tell the whole story. i use PVC boards with some insulation for the lids.
the nylon is guaranteed for 3 years in outdoor sunlight conditions and under high pressure of deep ponds so i guess i will grow old before i have to replace it indoors lightproof shallow conditions lol and i have a roll of it for cheap. my tables are about a foot deep.
enjoy!
