>From my limited understanding of the subject, the extent of the sterilization depends on the type of pathogen (and accurate identification is not a trivial matter) and the duration that the tank will be left empty (no fish = no host = no pathogen eventually).
Fish TB (if that's what it is), is not normally sterilized against. This is an internal disease which many fish carry and may not ever manifest itself until there are other stressors involved (old age, other pathogens etc). However Dropsy (a category of internal bacterial diseases) can have very contagious strains which need to be sterilized against. The generic method of reseting a seriously diseased tank is to remove & discard the substrate, filter media and water. Remove all ornaments and replace or wash in water with bleach, rinse and let dry (also the fish nets). Plants are replaced or sterilized in specialized solution (the name escapes me) though a mild bleach dip (1:20) can also be used on sturdy plants. Refill and add bleach to the water, run the filter for an hour. Then empty, rinse, empty, rinse, empty and then let dry. When you set up the tank again, double dose the de-chlor (against any bleach you missed). For 'suspect' tanks, same as above except replace bleach with hot water and allow everything to completely dry (dehydration is very effective at killing aquatic pathogens). Don't use hot water on your real plants though ;~) In regards to where to get fish... Guppies are notoriously fragile (bred in hot salted water, they are not expected to last long in freshwater at tropical temperatures). The Swordtail could have died from..? The 2st order of business is to match fish to your water. If there is some hardness and a reasonable pH, then Platies should last a while. Very hard water and you can add more Mollies. Softwater would suggest danios or tetras. New tank syndrome or osmotic shock would have weakened any new arrivals, causing a delayed illness. There are several aspects to answering your question thoroughly. hth NetMax On Sep 22, 1:26 pm, Kim <k_fi...@hotmail.com> wrote: > Hi all! > > I have been reading this site for a few months now and have learned a > lot. My husband and I bought our 6 year old daughter a 12 gallon > freshwater tank for her birthday in May. Of course it is my > responsibility to tend to it. We had 2 guppies, a swordtail and a > molly. We think the swortail, the last to join the tank was infected > with 'fish TB' and we are now down to one fish, the molly, I assume > she will start to show signs of illness soon. How do we clean the > tank so that we can start over? Do we need new filters, rocks, plants > (plastic)? Also, where do all of you buy fish? Petco's tanks are a > mess, ich, fin rot, dead fish. I got our fish at the LFS, and brought > home TB. Thanks!
