Hi Rika, Many of our customers ask the same question. So, to answer your question quickly, DON'T USE POOL CHEMICALS IN SPAS OR SPA CHEMICALS IN POOLS!
To be perfectly honest, the chemicals themselves may indeed be the identical product, but it's the labeling. And the labeling makes it a question of legality. The question of legality makes it a discussion of whether YOU want to be sued if another friend of yours gets a rash or "illness" because of using YOUR spa.
I'll be as brief as possible. Here's the scenario: you need to add "shock" to your water. You're out of it. The weather's bad so you go to your local pool discount store (you normally don't shop there, but it's convenient), go to the pool chemical isle (they don't carry spa chemicals & the store person is not knowledgeable) & pick up a bottle of pool shock; shock is shock (NOT). You bring the shock home & use it according to YOUR dosage of what you remember. A couple of days later a friend comes over for a soak. A couple of days later your friend calls to tell you about a rash that she's got under her arms, across her chest & back. She goes to the doctor, doctor tells her it's a good (bad) case of psuedomonas (PA). She spends lots in medical bills & presciptions. She wants to be reimbursed. An investigation finds that you are treating the spa with pool chemicals. The labeling says NOTHING about spas or hot tubs. YOU are negligible and therfore liable. You can also bring the store into this be casting some blame on them (not knowing better, should have told you, etc). You've lost a friend. BUT, you saved a couple of bucks on the shock!
That's why. Pool dosages & spa dosages are significantly different for obvious reasons. Another thing to keep in mind is that the way they are used is also much different. If you want some honest answers, you can visit our site at cheaphottubchemicals.com . BUT PLEASE, only use spa chemicals in your spa; NEVER use pool chemicals. In the long run it's not cheaper.
Enjoy your spa!
Chris