I have been reading about the importance of keeping my reservoir from getting too warm, in order to avoid disease. Coming from a cold place, it has never been an issue to me before. Cold basements seem to have sorted it out for me. Now I live somewhere hot, and the ambient air temperature is above 90 degrees fahrenheit, 32 celcius for weeks on end. Anyway, I was a bit taken by surprise at the prices of chillers that the aquarium guys sell. What do you think about me using a normal fridge holding a vat of cold water, and running my nutrient solution through tubes into it, around and around inside it, then back into the reservoir? I'd just poke a hole in the fridge door, and run the 2 tubes through, then fill around them with expanding foam. I think this would work. Now... if I'm KEEPING the temp down to 68 F, won't that be a bit of a shock for the old root zone every few hours? (flood and drain) - I thought we were supposed to be gentle with them. I'll be air conditioning the atmosphere to 89 F, and injecting CO2. Any comments from the learned would be appreciated.
Interesting idea. A simple solution for when times are hot and if you are worried about contamination in your reservoir is to just change the water more often. Add some H2o2 here and there and use a opaque reservoir. Should keep things clean.
I have one "Ice Probe" in each of my bubble buckets. It will only drop the temp 7 to 8f. If you have any humidity it will make the buckets sweat. I am not 100% sold on this idea just yet.
I also have High Avg temps of 30c.. I looked everywhere for a chiller, they were damn expensive. Someone said to me to use "Guardina Angel" as an enyme to prevent pyhtium etc. ANyone used this? I have sort of got around the high nute temp by using an external res, auto circulating the entire water every 30 mins for 10 mins. It has dropped the nutes temp a couple of degree. If i throw some Plastic Ice things in the external on real hot days it drops it a bit more. Not ideal, but cheap....
If its for your resovoir, buy a cheap bar fridge and put it inside and run the tub through a whole in the fridge with slack inside so you can open it and seal around the hole.
Before I bought the Ice-probe, I did a ton of research on low cost chillers. The dorm fridge idea sounds great but wont work at all. The heat transfer rate in a fridge is slow. Some folks tried to just use the coils from a dorm fridge to cool the nutrients, it never worked out the way one would think. For the same watts used, it would cost less to buy a real water chiller from a pet store. The Ice-probe drops the temps 7-8f. If you need more then that, you will have to put out some real cash for an aquarium chiller. They take alot of juice to run and cost an arm and a leg. Use the old fridge to cool beer in the garage.
On the journey to find a cheaper chiller... I found this, might help someone: http://cgi.ebay.com.au/ws/eBayISAPI...MEWA:IT&viewitem=&item=140088623408&rd=1&rd=1 , drops the temp 4c .... apparently. That would give me a nute temp of 22 -24c stable.. mmmm thinking about buying one Has anyone used the units,..... I am tempted for the ice probe, but my res has 75 litres and dont know if it could handle it....?
When buying a chiller, make sure you look at how much power that thing is going to take to chill water. The above chiller will use 300w to cool the water a few degrees. The price seems to fit the efficiency of that chiller. I have found 250W chillers that will drop your temps 20+ degrees, but you will have to pay over $300 US.