Yeah, is he perhaps a pool and spa dealer? Because many spa manuals explicitly state 'no trichlor'. It's hard to believe a spa dealer would tell you to use trichlor, which is pool stuff (I believe you, though!
)...
For one example, here's what SD's manual has to say:
IMPORTANT: Do not use chlorine tablets (Trichlor) in your hot tub. This chemical can have an extremely corrosive effect on certain materials in the hot tub. Damage caused by use of this chemical, or improper use of any chemicals, is not covered under the hot tub’s warranty.
