I'm dripping limewater every night to replace evaporate. It helps maintain your PH at night. Like already stated, don't drip too fast... I think the ph of the limewater is about 12.9 or close to it... a fast drip could drastically effect your PH. I usually drip about 1 to 2 drops per second. Also if you use Mrs. Wage's Pickling Lime, you are getting the same thing without the high cost of Kalkwasser from your LSF.... I"m not sure JFK Jr. likes Kalkwasser though ... LOL
Some of the stuff to watch out for.. 2 tsps per gallon of RODI water is all that can be mixed. More Kalk won't dissolve.. Also once mixed, let sit until the suspended particles settle on the bottom.. I usually let mine sit for at least 5 hours. Make sure that it is covered during this time... Then I just syphon off the clear liquid into another container and use that to drip into my sump.
I've been using Mrs Wage's for quite awhile and usually you can find it at the grocery store in the canning section. Hope this helps.....