I set up a mini greenhouse to allow for seed starting while the weather is cold, and for year-round greens.
The newest version of this system has small concrete mixing trays replacing the aluminum chafing dishes, which started to leak after awhile. I placed a water reservoir below the greenhouse, and use a small pump to maintain the nutrient water in the grow beds.
The greenhouse itself is one of any number of inexpensive greenhouses you can find on Amazon for less than $50 (link). There are a lot of em on Amazon, and they’re all basically made by the same factory. Look at the picture, details, and dimensions, and buy whatever’s on sale.
Each level in the greenhouse uses a small concrete mixing tray you can find at almost any of the home improvement stores (link) for the water basin, and has three of the 2-foot Barrina LED grow lights. (link)
The main water tank is a 27 gallon heavy duty tote. It doesn’t have to be that exact size, but it works well. I fill it up with 16-20 gallons, and that’s enough. Leaves several inches of wall uncovered by water.
The water pump is a HydroFarm 400GPH submersible pump. This uses 24W, and you’ll run it once or twice a day for 15 minutes. (link)
Misc Parts
PVC, fittings, zip ties
On my next build, I’ll keep the 1/2″ supply, but I’ll expand the drain to 3/4″ all the way.
Water Supply
1ea stick of 1/2″ schedule 40
@6ea 1/2″ tee
@6ea 1/2″ elbow
@4ea 1/2″ street elbow
@4-5ea 1/2″ ball valve
@4 1/2″ heavy duty bulkhead
Drain
1ea stick of 3/4″ schedule 40
@6ea 3/4″ tee
@8ea 3/4″ elbow
@4ea 3/4″ street elbow
@4ea 3/4″ heavy duty bulkhead
It’s always good to have extra parts on hand in case you mess up or need to make adjustments.
Oh, and one more thing. I used scrap lumber to build a platform under the greenhouse. The water and tote fit under that platform. I placed some scrap 2×4 under the greenhouse to lift it, and skipped the wheels that it comes with.
Because of air circulation and lights, you will need to refill the water reservoir periodically. That’s why I added the plumbing and pump. They keep water in the tubs under the plants. I just add nutrient water to the tote under the system.
For nutrient, I use:
MASTERBLEND 4-18-38 Complete Combo Kit Fertilizer Bulk (12.5 Pound Kit) (link)
In a system like this, it’ll last a long time.