Liquid Cooled Lighting

"Read about your liquid cooled setup and having 55 gallon drums. I am experimenting with a 32 gal res, and a homemade chiller, with 20 ft of copper tubing in the res, and a 5 gal bucket of water in the mini fridge. Fridge cant seem to stay ahead of the heat curve, but it slows the progression for awhile. Reaeding the posts Id like to know where to pick up 55 gal drums, and how you PVCed them together. Are they in series, with the output to the liquid lumens leaving one barrel and the return entering the last barrel in teh chain? I thought of that but was worried that there would be a back up problem of the PVC connection not being able to be equal to the pump output to the fresca sol I have. I am using a mag drive 350 pump, as the guys at the hydro store used a $25 Aqua 250 GPH pump which failed due to high heat (100F) int the 65 gal res they were using with a 1000MH. I have had so far after 12hrs, a 1000HPS heat the 32g res to 104F and ambient in the 3x3 hydrohut I have get to 95 degrees, and using a 400HPS, the ambient gets to 85F, and res temps at 100F.

Any input you have would be helpful."


For some reason I have gotten a couple of messages out of the blue about this so I thought I would make a thread and hopefully it will be useful for anyone who is interested. This site has and continues to teach me more every day, so if I can add anything I will be happy to try.

Ok so your using fresca sol, I have seen these at my new fav hydro shop, but I have no first had experience with them. I am using Hortilux super HPS, with this bulb it takes a large volume of water to keep a light cool. Ok anyway lets start with the basics.

If you have a 1/2 horse chiller a 50 gallon res is really the minimum imo, although I have heard with a res 125-175 gals it is possible to run it without a strong chiller, or perhaps without a chiller at all. I dont have any experience making a DIY chiller, but on a different thread someone suggested running a metal tube coiled up through a fridge or freezer, may want to try that instead of having it in the actual res. Also I feel its best to keep the res and the chiller/fridge/etc distanced a bit from one another.

Sorry I am a little scatterbrained =) I have a 165 gallon res, it is actually in a compleatly different room though it is not necessary, it is best to keep your res as far removed from any heat sources as you can if its possible, IE chiller/lights/CO2 burner, etc. Also insulating your res can do wonders. I'll keep it going in a minute.. gotta take a quick break =)

Im experiementing with a Fresca Sol right now. I am about to do a test run with a 50 gal res (got it at Wal Mart for 17.97, although it is a Sterilte tub, and very weak walled, I had to wrap packing tape in several bands around the short axis to stop it from bending, and with 450 pounds of water in it, I am going to place it against a wall and then support the free side with two five gallon buckets filled with water. Its all on carpet, so plenty of friction, this should keep it from collapsing.

I am running 20 feet of copper tubing in the freezer compartment of a 3' tall minifridge which is in the next room (hole in wall made with 2" hole saw). I would HIGHLY recommend using reinforced 1/2" ID tubing (Lowes - 0.82 a foot) as you cant aford to have kinks in your water lines that WILL happen from all the hot water moving through it (lived and learned). Then I have the tubing recirculating the water runing through the tubing back into the res (so two pumps in res, one to Fresca Sol, the other to the copper tubing in the freezer section of teh nextdoor fridge - ItsTime, I cahnged the setup after thinking about how they chill water in restaurants; water runing thru tubing in a freezer)

It seems in my 3x3' HydroHut I can get away with a 400w Hortilux HPS, the temp at 12" below the light is 85F, and at the floor, its 80F. Trying to get a 1000w HPS Hortilux in there, but I dont think the DIY chiller I made will cut it. Guys at Fresca Sol said that they are having trouble with 1000W lights in anything less than a 100 Gal res with a strong chiller.

Remember, the water does not DISSAPTE the heat produced by the light, it only ABSORBS it in transfers it to somewhere else, i.e. your res. Then that heat comes right back on the return loop. IF you are in an area where you have cold temps at night, or at least breezes, putting the res outside somehow would enable nature to cool the water at night when your lights are off, then you have a constant chiller running, otherwise, you have to have a res so large that it can absorb all the heat PRIOR to the 12 hour mark coming along before the lights go off. IF you never had a chiller, and kept the lights on 24/7, no matter how large a res you used, without outside influence on res temp, like a chiller, or cooling at night from an exterior res, eventually you will reach intolerable levels in your grow space.

***Of CRITICAL note: Until you get a good sized res and a strong chiller, DO NOT experiment long term with a standard recirculating pump like an Active Aqua or such. The res temps can flucutate so much even when you are happy with your grow room temps, that the water can get up to 100F with a 1000W, or around 94 with a 400W, (this was with a 30 gal res, Ill let you know how the 50 gal res fairs) and if it chills down to 77F at night, then you are subjecting the plastic pump to extreme temp swings, and the plastic will fail, stopping your pump, heating your water cooled light (no circulation) and your glass with shatter due to the heat buildup. This is exactly what happened during a test run I witnessed. Use a Mag-Drive pump that is serisously overbuilt, can withstand the temps, and can even be used as an inline pump without being submersed in water. Otherwise you are playing Russian Roulette with your whole setup.

I will let you all know the figures when I complete my test runs.