I used it today and basically my tube water turned faint blue/yellow at 8 drops~8dKH. But it wasn't bright yellow, IMO, until around 11-12 drops. Photos here.. My tank thread. The ALK vial is first one in the right. Is that bright yellow? Sorry for crap pics. iPad.
Anyone with experience with these kits that could help me out? It's just so confusing, my bright yellow may be different than yours .