Here is a test of the one of the mini submersible pumps I ordered last week. I picked up 10 feet of vinyl hose to connect to the 7.5mm connector on the submersible pump.

I was thinking of using tin cans as a transfer medium for the plants from the seedling stage, however after a bit of testing I've found that the cans are rusting. Not ideal long term, however they would have worked nicely as a thermal heat exchanger.

I am now looking instead at 3D printing a soil based vertical planter setup. The reason for this relates to simplicity, the horizontal shelves just aren't working out. The 1x4 boards warp in the sun, they'd also be quite difficult to level consistently for an end user.

An update to the initial project sketch will likely be happening in the next week or so as I am still waiting on the soil moisture sensors to arrive.