I had heard great things about the TLF C-balance.  I went out and bought a set.  It comes with part's A/B in one box.  I am now just about finished my bottles.  It has been an excellent way to maintain the ratios in my tank.  As a supplement to my kalk I've found that I have to dose about 1 capful of each part daily.  This past week I tried 1/2 a capfull but unfortunately my levels dropped a bit.  Both parts dilute quickly when added to the tank.  I was having some excellent growth, the most I've ever seen in my tank up till the blackout occured.  Since than my sps have been on a recovery and readjustment period as the blackout threw off a lot of my rituals, especially since I had guests over at the time.

I would rate the product very easy to use, and provides excellent results.  I may have to use it for a few years until I can save up for a calcium reactor.  Unfortunately the only downside I've noticed with the product is it gets fairly expensive to use.  Perhaps if it was a little more concentrated it would help on cost.  I've found many calcium products on the reef market too diluted.  1 scoop/capful raising calcium by 15ppm/20gal of water is too weak IMO.  If I moved to a larger tank this would be totaly unreasonable.

I would recommend this product to anyone running a nano, or as a stopover gap on a larger tank before you add that calcium reactor.