Drains for poly drip pans + gritty mix?
Over the winter I put quite a few plants into the gritty mix. All of these plants overwinter indoors - some in an unfinished basement, some in finished areas of the house. The plants in the finished area all require drip pans. The problem I had was whenever I went to water I always had quite a bit of water go right through the mix (the whole point, no perched water). However eventually the water would build up in the pan and would overflow unless I could get in there with a syringe and suck it out. This became time consuming. Many of the plants are too heavy to lift every time I want to drain the excess water.
What I've decided to try to do is build little drains with shutoff valves into the poly drip pans and either connect them all together or just use a bucket and open the valve when I need to drain them. The problem is that I can't seem to find a fitting that will lay basically flat against the inside of the drain pan (as flat as can be on the curved surface, I will put silicone in behind it). Does anyone know of anything that might work? I need something with a *very* small profile on the inside of the pan since almost all of my pots use the built-in drip pans that just barely fit. Then I need a way to connect the grommet or flange-type-thing to 1/4" tubing.
So far these look like my best bet:
Even that grommet doesn't look like it will be thin enough on the inside - not to mention it's about 2$ per pot with the valve...