Testing For Hardness

There is. I know API make a GH and KH liquid reagent testing pack and I expect other makes do too.


The API testers work differently from ammonia etc, though as you use strips you won't be used to liquid ammonia etc testers. Ammonia etc liquid reagent testers work by adding a set number of drops, waiting a set number of minutes then comparing the colour of the liquid to a chart - strips are similar in that they require the user to compare a colour to a chart. The API GH and KH testers are different. You add 1 drop, shake and see if the liquid has changed colour. If not, add another drop, shake and see if it has changed colour. You continue like this until the colour does change, and the number of drops it took = the hardness in German degrees. Other makes probably work the same way.

Ah, I thought you meant you used strips for everything. Sorry for the misunderstanding!