Mardel LiveMeter Master Test Kit

Test liquid should be good for atleast 2+ years unless you end up buying old stock. Those in tank things need to be replaced every 3-6 months. I'd rate the in tank meters at less reliable then paper strips, I know it took about two days for an ammonia one to read 0 after being elevated then water changes done to bring it down to 0. If it took two days to go back to 0 how long did it take before it even started showing the original amonia readings?

In short no way I'd replace liquid tests with one, maybe if you want to monitor ammonia between tests get the $5 seachem ammonia one.
 
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