Oh please - don't you love the know it alls who can't simply say "sorry, we don't carry them but a little ST will do" without adding a dig... I guess you are not a serious aquarist, now go sit in the corner and rethink your evil ways.
BTW - genius boy is wrong, chlorine levels in the tap vary daily depending on what's going on in the water supply, the part he got right is that Sodium Thiosulfate is pretty idiot proof (ie, I have used it successfully thus you can't miss).
Oh well, here's a test kit on Ebay that looks good:
http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... gory=20684
The good news is that a drop of ST will do gallons of water and the sprinkler actually removes some chlorine (aerating water removes it fast)... My guess is that if you can setup a ST drip you will get the job done - no need for precision here.
Cheap too! You can make a gallon of concentrate by using 4 dry ounces of ST and then 1 drop of concentrate per gallon of tap water so if you get a bucket here:
http://www.chemistrystore.com/sodium_thiosulfate.htm
for $4 whole dollars for two pounds it'll make 8 gallons of concentrate which will dechlorinate Texas for a month. Not sure how many drops are in a gallon but I'm guessing one gallon of concentrate would make my pool dechlorinated in about 5 minutes.
OK, spending way too much time on this but ya got me curious - y'all have water from aquifers and the water filters through calcium carbonate like I figured - you have hard alkaline water which is why the rain does so much more.
here is your contaminant report:
http://www.saws.org/our_water/waterqual ... arts.shtml
Don't freak out when you read it, that is actually 'superior'.
In answer to your next question, Walmart has 2 gallon jugs of distilled water with a spigot for drinking pretty cheap and an under-sink RO system is down to $109 on ebay and this one looks good -
http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... gory=20758
I used to design the things and they are a lot better these days - look for 3 stage filters - 1 micron sediment filter, activated carbon (smell/taste takes out dissolved organics as well as all those 12 hyphen chemical compounds in the water from pesticides) and the RO membrane - basically that allows only pure water through and removes all of the dissolved salts. Way too expensive for the yard because they typically waste 3-4 gallons of water for each pure gallon made (run it right into the garden) but great for drinking and mixing home brews..... just be careful - any microbe living in very hard water will likely explode in RO water when the pure H2O runs into the cells to dilute the harder water... sometimes a spoonful of epsom salt to replace some hardness is a good idea.
Far more than you wanted to know... am I procrastinating getting my work done today or what.