I didn't start seeds in my kiddie pool but it works well for daylily seedlings and seems like it would work for seeds.

Mine was started with leaves in the bottom, some partially decomposed spruce needles, some top soil, and a lot of alfalfa pellets. Depending on what king of seeds you're growing, it would probably work if you put a cheaper soil mix on the bottom and then a bag or two of seed starting soil or grow mix on top.

Frillylily said:Wondering if I can use the Miracle Grow Moisture Control Potting Mix?

Who thought buying soil would be so complicated

That Miracle Grow soil works pretty well if you pick out any big chunks, and if you mix in some sand. The sand makes it a lot easier to prick the seedlings out to move them to 4-packs or paper cups etc. as they get bigger.

My brother bought a huge bag (but smaller than a bale) of Pro-Mix BX potting soil. It is peat based with a lot of perlite and/or vermiculite and inoculated with beneficial fungi, and it seems to have a wetting agent added. He has some seeds just coming up in the stuff now. I really like it, and will try to find a bag when I get home. (currently self-quarantined in another state) But it's pretty expensive. The price doesn't look too bad here, until you add the shipping: https://growhouse.supply/produ... Your local Ace Hardware might sell it if you're lucky; it shows up at their site online.

ETA: start the seeds in cut-in-half milk cartons, or cottage cheese containers with holes punched in the bottom (use a hot ice pick to poke the holes) It's a lot easier than what you're talking about with the pool. The pool might be good for a few plants when they get much bigger.