I have a bromine hot tub that I am having a hard time keeping any bromine level available. I am using MPS to shock and adding bromine granules. I have the spa frog system but haven't really been using it as I was advised that it was not very effective on this forum. My question is: Can I use the bromine cartridges as a floater to keep my bromine residual up? Is there any advantage of using the mineral cartridges? I have about ten bromine cartridges left and three mineral cartridges left. I hate to let them go to waste.