for a couple of months now i have noticed that the drain in my shower, and bathroom sink have a blue tinge to them. i'll clean them off and then they will return within week. can someone tell me what this is and what its caused from. Thanks

I think my question is a bit different from what I have seen. We have very good water pressure at our ranch/slab house. We also have a septic system. Here is the problem. In the winter, at night, if I use a hard shower, we "sometimes" get a smell. If I lower the amount of water I use, we seldom get a smell. If I take a shower during the day, hard shower or not, no smell. If I take a shower night or day during the summer time, no smell. We live in central Alabama. No desert no snow. Lots of trees. Winter is usually wetter, but not extremely so, than summer. The other thing is that the smell comes from the master bath (This is also the master bedroom). And is indeterminate. I.E. Can't point to a drain or fixture that the smell is coming from, it is just there. Also, this occurs if I take the shower in the guest bath. If I take a shower in the master bath, there is not a problem. Any assistance greatly appreciated.