new/used fish tank

Question
ok admitting I'm an idiot is not the easiest thing to do so i come to you for an answer to fix my major mess up, i bought a used 50 gallon fish tank, it was looking really nasty and the guy said he used it as a live bait tank in his garage after trying to clean it up with just water i went against what i know is wrong and used some lysol disinfectant cleaner on the inside of the tank and finally got the tank cleaned really well, rinsed it over and over for well over a half hour to make sure i got all the cleaner off the tank before setting up, i know idiot move number 1 used harsh cleaner on a tank, now for idiot move number 2, i did not research the side of my tank and by looks of it thought it was 100 gallons when it was only 50 gallon so when i put the start zyme stuff in i used double what i should have used, obviously the combination of the 2 fatal errors did not turn out so well for the 10 starter test feeder fish i bought to see if the tank was safe for better more expensive fish, without about 2 hours all 10 fish had lost their color and died, what can i do to fix this problem so my next set of fish i get have a better chance of living

Answer
Hi Eddie!

Ok, first of all, remember to NEVER EVER use cleaners of any type no matter how mild it may be on any aquarium or tank. Right now, the best thing you can do is to drain out all the water and rinse the tank thoroughly. To see if the tank is pure, fill it with water and wait for a few hours. If there are bubbles or white stuff in the water, then you must rinse the tank again. Washing the gravel and decor. in the tank will be essential in this process. When the tank is pure, you may add water again and use your starter kit. Just don't over dose any chemicals and follow the instructions strictly.


Hope this helps! XD
~Sam