I have this res temp problem and I need to cool it. I read that copper tubes are bad to mix to with your res and discovered that I can use stainless steel. There are different types of it and they recommend using those in the 300 serie like type 304 or 316 the marine grade type. I cannot a wort chiller online because I do not have a credit card. I decided to just buy one 20 ft tube, cut it several times then connect them with my hoses in which cool water can pass through. So I came to the local hardware store and they do not know what I'm talking about. (I live in a 3rd world country) What they keep telling me is that the metal is non magnetic (type 400 are magnetic while type 300 and type 200 are non-magnetic). I looked at the label and there are numbers, codes and a barcode but I do not know what to look for. So what I should look for in the label?
You might be better off taking a coil of stainless tubing and running cold water through it and lowering that into your reservoir to cool it. http://www.aksteel.com/pdf/markets_products/stainless/Stainless_Steel_Comparator.pdf
buy a length of 316 and take it to a local fab shop and they will roll it for u shouldnt be too expensive. i think 316 bends nicer than 304 but i know its a little harder to weld.
Copper is bad to use unless you do something. I can't recall at the moment, but if I'm thinking correct it was some what like pickling it . I'll get back to it.
save your self and go buy a prepaid VISA debit card I dont know what you mean by a 3erd world country but you you can buy prepaid cards in a lot of gas stations,supermarkets walmarts,they are sold just about everywhere,just make sure you get one you can use for online transactions and your all set,I know here in the US a 100 dollar card costs 105.95 they come in 5,10 25 50 75 and 100 dollar cards...
Use 1/2 white pvc tubing and coil it to the size you need to fit Resavoir and then tie it in 3 places to hold the coil in shape and then connect it to a cold water source
Dont worry about the numbers they are for welding so buy any stainless pipe they have you will be fine to if they have aluminum you could use that too mite be cheaper