Baby Bottle Sterilising Tablets Or Fluid

We have a new born baby (6 days old and gorgeous).

I bought a microwaveable baby bottle steamer, my wife is trying to breastfeed but encountering some problems so on occassion we have had to give the baby formula to stop her dehydrating. Trouble is with the microwave steamer when you take it out everything is so hot and theres so much steam it turns the place into a sauna, plus if you only want to use one bottle they say the items sterilised will stay sterile for 3 hours as long as you don't open it...which says to me once you've taken one bottle out the rest isn't going to be sterile long.

Anyway what I want to know, and I've tried both Paragon and their supermarket to no avail (I was sold something for washing vegetables in one instance and offered some electric hob cleaner in another) is where can you get baby bottle sterilising tablets, or fluid, like Milton in Bangkok, just think it would be so much easier to have bottles soaking in the stuff which you can remove and use when you need them.

Any help appreciated.