buying advice

Hi, all, I work at an outdoor educational facility on the coast of California, and I've been tasked with resurrecting our touch tank that we use with students. Over the past year, I've worked with an aquarium technician to get all the parts replaced/functional, and now I'm entering the process...

Anyone point me in the right direction on where to buy bulk phytoplankton, looking for 7 gallons. Preferably a hobbyist or smaller business first. Thank you in advance.

I've seen BRS reccomends the Hanna Checker Plus pH Checker, it seems to be a popular product, but I've also seen negative reviews I already have the Hanna Marine pH colorimeter, but that has an accuracy of ±0.2 pH, I got that because it doesn't need calibration, but I've noticed that there're...