The Puffer Forum

Hello! I have created this account literally in a time of need. We have a 5 month old tank. And about 3 weeks ago bought spiny box puffer that’s about 3-3.5 inches, and a Powerder blue tang, about 4 inches. At purchase, the puffer had a loose skin/an abnormality on one his spikes, which I initially thought was due to it being bitten in its previous tank. Over time , the puffer has gone from white to a grayish tone. We do weekly water change of about 25-20%. In Our last water change, I believe my boyfriend added too much Bacteria. We woke up to our tang being dead. And our puffer laying at the bottom in really bad shape. (We do not yet have a QT tank. If we started one today, would that be bad due to new tank syndrome?? ) we did about a %30 water changer, allowing salinity to lower, added API antibiotics And waited it out. Few hours later the puffer was up, and happy and swimming around and feeding and nearly back to its regular color.

as of this morning has another another deformed spike right next to the other. He is taking slightly gasping breaths. And not as responsive to our present on the tank, and color is horrible I have attached what he looked like at purchase and how his is looking now. Parasites? Marine ich?
Ammonia: 0ppm
Nitrate: was 80ppm , now 20ppm(still high, I know)
pH: 8.4
Temp: 74.6

Any ideas of what’s wrong? what we can do?

Bent/shedding spines are normal.
Any nitrite? SW systems are best kept stable with live rock. A cycled tank should not be needing bacteria added. Please don't toss drugs into the tank when you have no idea what is wrong with your fish--also, adding an antibacterial can crash your system.
Are these the 1st fish you've added? How was the tank cycled?