I will not trust a seachem badge (also for freshwater) and Api kit to sustain/maintain Hundreds in Livestock. I recommend hanna, salifert, nyos brand for reliability. If none of these available in your country, SERA would be next choice
I too have heard and seen. When you get a test strip and get it wet, you have 30-60 seconds for accuracy. Then how does a felt sheet which is manufactured for fresh and salt water maintain accuracy when wet full time and subject to chemical exposre remain accurate?
I believe the first week or two, will offer good reference but afterwards and exposed to chemicals such as copper- No