Stocking an aquarium

Question
Hello, I have a 40 gallon tropical fish tank sadly we are losing our fish as we cleaned the tank with a sponge and never knew it had a anti bacterial wash in and has poisoned our fish we have cleared the water and at the moment I am left with 2 blood parrots and 1 tiny gold gourami.. We are thinking our parrots and gourami will die die to the poison being in there system.. How do we Save them ? Is there a chance? If they all die how long till we add anymore and make sure nothing bad is in the waters.. Also if they survive what nice and vibrant fish can I put with thEm. If they die what can I put in? Mainly I would like a discuss? Or angels.. But I would want a shoal of something and either neon rainbows or I'll get some bosemanis and the ones with the stripes.. When we cleared the tank with cleaned the filter and whole tank so no poison is present that is our worst mistake ever we loved our fish :( thanks x

Answer
Hi Alex,
All you can do is a 30% water change, and 10% everyday, and hope for the best.  If you know someone, or a pet store that would keep them for a while, then maybe they will live.  
If your fish do not make it, the poison in your water must be removed.  The only way to do this is to start over.  Empty your tank, wash your gravel well in warm water, fill, and empty the tank until you are sure there is no poison left in it.  Clean your filter, and ask your pet store manager for a used sponge that fits your filter to help bring good bacteria back to your tank.  This may take another 3-4 weeks before you can add a fish.  Your tank must cycle again.  There are no other solutions.  I wish there were, but when things like this happen, we must have courage, and start over again.
Discus fish should be kept in a 60 gallon tank.  They need soft acidic water, and the water must be well cycled.  It is very important that their water should be without ammonia, nitrites, and nitrates have to be very low.  Discus fish should be kept with neons, and rams.  Many people run their water through peat moss to keep it acidic.  Never use chemicals to bring down the PH, they would do more harm than good.  Driftwood may help keep the PH down.  Read all about Discus fish on the web, or buy a book on them.  Gather all the information you can on keeping these fish before buying them.  I do not have the space to write this all down here.  Angel fish need 10 gallons of water each.  The bosemani rainbow fish lives in groups of six.  Two males to four females, and more females is best.  They are good swimmers, and the longer the tank the better.
I'm sorry this has happened to you.
Best of luck..
Lynda