Originally Posted by labloverl
I have an API test kit and so far I've broken two test tubes. Plus they are stained yellow from sitting with the tested water for too long. Anything I can do? I've rinsed with vinegar already...
You can purchase replacement tubes on Amazon. You can remove the stains with a drop of bleach diluted with some water then rinse really well & let dry completely. I always rinse them really well & use a paper towel to dry them out when i get done testing which helps get the residue out.