This is just a theory, so take it for what its worth. I would not provide chlorinated water BEFORE the bees find the pool. I'd find another nice smell for your alternate source (lemon grass, HBH, etc - small amounts only). The thought is that it might be better to differentiate the two water sources. If they both smell the same, then the bees may treat them as the same source, since they are relatively close. Now, its completely another matter if the bees are already in the pool water. In that case, I would provide chlorinated water (pool water directly) at an alternate site. This way you might have a chance to pull them away from the pool. Its far better to train them to your preferred source BEFORE they start using the pool. As a pool owner, I can advise that you need good pool practices, that is, wet towels, pool toys, etc need to be put away after use. Don't provide any bee-friendly landing sites in your pool area.