I think one solution is to get a used small unit like in motels. Adjusting and controlling nutrient
temps can be done by altering the length of tubing inside the fridge. More tubing, cooler temp, and vice versa. A certain amount of fiddling around needed to get the temp right, maybe making in-out holes in the fridge,etc. I got a unit at a yard sale for $30. At this price, I can buy one a year if I have to. Hope I don't have to. Conservation of funds is necessary
for me.Please, keep your suggestions and comments coming.Encouragement matters!