old tank to new now big problems

Question
hello my name is corey i had a 29 gallon tank i just puchesd a 75 gallon tank moved my fish to that new tank with old filter new filter new gravel new heaters old air pump for a 20 to 40 gallon pump one day i lost 2 fish and almost my shark and algae eater there very big and i don't wont to lose them so i went to pets mart and bought tetracycline and aquarium salt day two there still alive but my tank is still yellow and foaming at the top and it wants me to treat once then change water then treat again what do i do my shark looks better but his eyes look bad i don't want to put to much ems can you help me please

Answer
Hi Corey,
I believe I would stop medications for now. I'm not exactly sure what you are treating for. But from what I read the shark may have swollen and/or cloudy eyes? If so, often this condition is a symptom of poor quality rather an actual disease. I do suspect poor water quality since the fish have just been transferred to a new tank (keep in mind even though transferring the old filter and gravel over helps, the tank still has to cycle), so I'd definitely recommend starting a water change regimen of about 50-75% everyday and stop all and any medications (Salt isn't necessary either).

Continue this until your fish are better. If you could test your water for ammonia, nitrites and nitrates that would be wonderful.

I do hope all goes well and best of luck!
Karen~