DIY chiller. ok Im going to try and explain this as easy as I can, its really very easy once you think about it for a bit.first this will only work with a system that has a res,my system consists of indavidual 5 gal buckets that are all linked togeather with a res. now you can use an ice chest for your res thats what I used. now all you need to do is get a pond pump mine is 400 gal. an hour,you hook the out line to your tubing that links them all togeather.now this part will take a bit to get it where you want,fill your res with plain water to get it dialed in,its best to do this before you are up and running.now all you have to do is set a timer on the pump to come on and off as many times you need it to to keep the solution at or near the temp you want.you will have to put frozen water bottles in the res to maintain your temp it will take some time to get it dialed in but it beats putting the bottles in the buckets everyday and having the res for me makes it so much easyer than trying to add to the buckets everyday,my plants are drinking 3/4 to 1 gal. per day now 3 weeks into flower and it would be a pain in the ass if I had to add to each 1 now I just top off my res and you can check you ph and ppm from the res to. I hope I explained this well enough if not ask me what you ned to know peace and grow on