Generally speaking liquid test is more accurate than strips, but neither should be considered as an accurate test. They are home test kits, not laboratory testing.
Im going to duck out a little bit and suggest you post something in the invertebrates forum as ive never kepf shrimp. KH
of zero. A little reading around the subject indicates that your shrimp prefer really low KH
, 0 to 1 KH
But with zero KH
your system cant buffer any acid that goes in and your pH will crash, causing pH fluctuations that wont be healthy for any living in there. pH reducers are essentially acids and i would expect them to have a very noticable effect when added to water with zero KH
. Respiration and the nitrogen cycle will also acidify the water over time. No KH
will result in a pH crash.
Like i said ive never kept shrimp and ive never had to manage such extreme water parameters, so you may want to post something in invertibrates where its more likely to get seen by someone with experience of keeping these shrimp and how maintain a suitable environment. Maybe something you are experienced with dealing with already, in which case id love to be educated a little.