The Puffer Forum

Firefox is a SW fish. Try H2O2 dosing: https://www.aquasabi.com/aquascaping-wi ... e-aquarium

library/puffers-in-focus/an-introductio ... d-puffers/
library/water-filtration/emergencycycle/

Most BW fish are sold in freshwater. Tetra Safestart is good. You can add it directly to your filter & then add the puffer. Check the parameters fir 2 weeks & if everything remains stable, you can begin adding salt. RODI is not necessary.

Hi, Images are not coming through. You have to load them to a photo storage site & then link them here.
I feel you are adding way too much salt; no more than 1 tbsp/gal.

I wouldn't worry about 2 dots. Ich appears like your fish has been salted.

If there are no spots on his fins, what you are seeing are his tiny spines.

All your answers are correct, considering a singleton can live in a 15g.

How is he doing now? Nitrite of ANY amount is extremely toxic.

Is it getting larger? Is it circular & hollow in the middle?

Fast him as long as it takes to get him to eat something else. Try live crabs. For constipation, treat the tank with Epsom salt at 1 tbsp/5g.

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Here's a great article: https://www.pufferfishenthusiastsworldw ... care-sheet

Parameters, please

I need the rest of your parameters.

Your pH is very low. Lower than urine. What is it from the tap? Any tank mates? How did you cycle the tank?