I have tried with very little success to grow spinach in hydro. Lettuce is easy but spinach is trickier to get to germinate and it is also prone to rotting if conditions are not right. I read a paper about growing spinach in hydro on a comercial scale, I think it was done at a university somewhere. I do believe spinach likes cooler temps so 80 degrees might be a little challenging. Perhaps you can find a variety recomended for warmer climates or that is slow to bolt.

Good luck

Ill let you know howmy Spinach growing goes. We are trying to grow stuff not likely grown in PR. Ill do a little more research n it and get back to you. Thx for your input.

Rocc

I grow chard (spinach?) all year round. pH is critical (6.5 - 6.8). Grow seeds in moist sawdust untill established. Transplant into sand/sawdust mixture. Then grow-on in an ebb&flow system. They want LOTS of moisture in hot weather.
I harvest leaves every 2-3 weeks.

chard is not the same as spinach; it is more heat tolerant. Probably would do better in PR.

Spinach likes cooler temps - 60'F or so. 80 would be very hot for it and it would likely bolt quickly. You'd need to figure out someway to cool the plants down. Perhaps if you gave them tons of nutrients so that they grew really fast you'd get a harvest before they bolted. It'd be tricky though.

I've had great luck growing spinach; plant now and have the fresh stuff until about May. I use a flat leaf variety, "Space" that I get from Twiley in SC. It looks like the "baby Spinach" sold in packages. Here in central Texas we have a mixture of hot and cold from now til Easter and the plants did well, sleet storm didn't slow it's growth.