Hey everyone, i wanted some opinions on the best, cost efficient way to cool my reservoir water, because i dont necessarily have $300+ to spend on a water chiller right now, but i fully understand how important it is to have the water under 70F, so my main question is, if i got an aquarium temperature controller with a submersible probe, could i essentially build a cheap water cooler by utilizing the temperature controller plugged up one pump in my reservoir pumping water into a tote full of ice and another pump in the ice water pumping water back into my reservior? The way im thinking is if both pumps are the same brand, same water output, are plugged up to the controller and turning off at the same times at 65f and turning back on at 60f, and the same amount of distance to travel from one container to another, and 7 gallons each in each tote, both totes being exactly the same dimensions, that i shouldnt have any issues with water level fluctuations? Would i be correct in assuming that? If i can make something like this work, i could have a functioning chiller in a week, rather than not having one until my next grow and risking the health of my plant. Photos for tax purposes
I think it can be done. I have plans in my head for a small dorm room fridge and a roll or 2 of copper tubing.
That would definitely work! But unless you get a used mini fridge, youre still gonna be investing a small but still decent amount of money into a mini fridge, but i like that idea, the reason ive thought up what i did is because i already have everything at home to build what i described except for the aquarium temperature controller that i can get shipped in a week for less than $40
Look for one on Craigslist and that ought to work. Not understanding your setup but normally RDWC has a check-rez that is filled on demand to maintain liquid levels.
Exactly,$30-50 all day long. Except the day I look lol 
Maybe even free if I hold out long enough and put enough feelers out.
Everything else is already laying around here somewhere.
Here is a photo of my set up currently my main concern with my idea was just potential over flow, i love to DIY and will with anything that i can, im not sure what id have to do with the mini fridge idea to make that work but id be on board to try to figure that out!
I would look at different designs for undercurrent RDWC systems to give you a better idea of how to set up your totes. Keeping a check-rez in the system will maintain proper liquid levels. It is filled from a larger reservoir from a float valve in the check-rez.
what is your reservoir nutrient temperature now???
I am currently freezing dozens of water bottles and putting them in my reservoir about 3-5 at a time, and it drops my reservoir temps to about 60-65f, and im trying to be as consistent with that as possible! But without the frozen water bottles it was sitting at 75f, i am getting a used full size fridge/ freezer from my co worker on sunday, and i will be figuring out using that to cool my water more consistantly, not starting another grow without a legit chiller though, the water temps have been a nightmare for me. And now my EC is spiking high, and ive got a small amount of nutrient burn (i believe) i will post pictures of the area of concern in a few minutes when i can get back to the room if anyone can give me a definite answer if it is in fact nutrient burn, and if it is, do i just need to flush the system then re add a smaller amount of nutes?
I went ahead and did a full system flush, including fox farms OMRI rated organic sledgehammer flush formula, I let the old water sit with the sledgehammer formula for an hour, then completely emptied the reservoir and added fresh filtered water, then proceeded to ph and add nutes at an even more cut down rate, my PPM is now sitting at 685 instead of sitting around 1000.
I guess I am lucky that my reservoir/tanks mostly stay below 69 deg on the floor in my bedroom…I also have never ran PPM as high as others and nutrient manufactures say to do…I start with 0ppm water and at my highest mark hit 700ppm the first couple weeks after flip…I completely change out my reservoirs every 7 days …every grow setup requires different needs IMHO
Yeah, before i changed my reservoir the nutes in there where the first nutes ive ever supplimented, had it up to the high 800s when i first added, then it shot up to like 1,300, then last night i started noticing all the browning, now i cut the dosage down after changing the water started in the high 600, and is now in the low 700s and so far i have not seen the browning spreading any further!
in a contained reservoir system like mine and I believe yours…the plant can drive the PPM level up as well as down while consuming water…
I used this old steel plate that was laying around in the way, in the garage. Placed it under this reservoir on the concrete floor as a heat sink, and it fit very well in the recessed area of the bottom of the tote. This dropped the reservoir temperature by 4 degrees.
About using the refrigerator and tubing in a previous post. I wouldn’t use copper tubing, since you will run a good chance of the copper leaching at the ph that you will need to run. I would use vinyl tubing, and you may need to use more of it or go with a larger diameter.
Also I have seen an online video, where this guy used a cheap dehumidifier, and unfastened the cooling coil while leaving the refrigerant line connected. Then bent the tubing so that he could drop the cooling coil into a reservoir.
For some reason the dude felt it necessary to cuss out the manufacturers of chillers while making the video. But there is no way that I would drop a copper cooling coil in my reservoir.
If you look at the specs on a good chiller it doesn’t use copper for the heat exchanger in the water side, another reason for the price.
I have come to the conclusion that i will be building the chiller with a refrigerator my co worker is going to give me on sunday, i am going to be running 300-500 feet of vinyl tubing inside of it, coiled around itself, so the water has adequate time to cool, and right back into my reservoir, i sadly have my grow room in a bedroom with carpet, so the floor stays pretty warm
I think that I would start off with a 50 ft roll of 3/8 or 1/2 inch. The 1/2 would probably slow down the velocity enough for a better heat exchange.
1/2 inch is the plan! I have a very small pump with a 1/2 outlet, that should be able to pump the water through that much tube, it would pump it through really slowly too, giving it that extra time to cool