The only possible explination that i can think of is some sort of chemical got into the water, considering the quick deterioration of the fish and the quick recovery of the clowns. I did a water change yesterday and i used a bucket from my friends house. Maybe there was something in the bucket even though i rinsed it well and i am pretty sure he uses it for his tank too. Any other possibilities that anyone can think of???
I am sorry for your losses .
Sounds like contamination , I would just go to a dollar store and get a bucket ,rinse well and mark it so that there are no mistakes on it . I had a posoning in a 2.5 gallon , I had been cleaning and using the clorox clean wipes, I bumped the stand and with out thinking I stuck my hand into the tank to fix a coral ..... long story short I had forgotten that I had used them a bit earlier with in a half an hour our Mr.Wiggles was on the bottom of the tank and breathing with all his being , I could not figure it out , so I set up and started to drain the tank ... went scrubbed up and rinsed well donned rubber gloves and got the air pump out set it up changed all filter media out , placed a second filter with media in as well every day I placed in new fitler media ,I did a 40% change right away and dripped it in over a period of 1/2 hour I did this every day I kept the lights on an abbriveated schedule 3 hours aday the rest of the time just the moons , on over the period of 2 weeks I did H20 changes every day as well as the media . Happy to say every thing but the coral that fell over survived , the other thing I used was a bit of bio-spera to help , I also kept the air pump on for 2 weeks then I did my weekly changes of 50% for the next few months , now I am back to 1/2 gallon a week .. It is possible to have a posoning and not lose it all . I wish you the best for you and your critters , but dont blame yourself as these things happen , now I always wear gloves and if any equipment has a question of contamination I trash it .HTH