Hello! I have a 20 gallon long that I have been successfully keeping some neocaridina shrimp in. I've been toying with the idea of setting up a small shrimp only tank. First step in that for me would be getting a TDS meter. Which one would you recommend? I'd like a not-too-expensive one, but I'm willing to splurge a little if all the cheaper ones suck. Thanks in advanced!