You may have to order the kit online, which will be more expensive shipping to Canada. However, it will be the best investment for your tub that you will ever make. To be honest, without it, you will have a hard time maintaining your water.
The best thing to use to clean your filter is Trisodium Phosphate (TSP) which is found in some dishwasher detergent. However, being in Canada, I'm not sure what's available. You might find a regular filter cleaner in your local spa/pool store.
Don't use acid unless you have scale deposits on your filter. If you do have scale deposits, make sure you clean the filter with a filter cleaner before using acid, or you wil ruin it.
Thanks Nitro, you are amazing!!! I will try to get these things and i will post you on how its going.