KH Guardian isn’t “fast” due to safety tests it performs 2-3x before taking the actual reading. I will say on demand kh test takes 10-15 min.Based on above all reading and info,I still trust reagent based device better.
Is more less complicated.
As for aquawiz Per test is about 40 to 60 min, this a long time for a result.
If results are drastically different than the last test - it repeats everything to see if there was a testing error
Reagent pack is 20$ + sh and lasts 2 months with daily testing every 4 hours. Reagent is a liquid concentrate you mix in with 1500g of rodi. I like this as there’s no powder to dissolve or settle