The Puffer Forum

Tim; Very true, when you go on youtube you see people with their GSP's in freshwater. Personally, I find it better to put it in full marine at a young age with a very slow drip acclimation, and if you buy the fish with parasites the high SG kill's them.

The F-8 study was quite a while ago, but it was pragmatic- that means I tested multiple densities and checked the results with out pre-concieved ideas. All fish were individually housed in 15 US gallon (nominal) tanks, but actual water volume was somewhat larger (sumps were shared by 2-4 individual tanks. All fish had sight of conspecifics. Longest lives (elapsed time in captivity in my tanks) and health (subjective in part - activity level and appetite were parttially subjective, coloration was on coded scale).

Longest life spans were at 1.003 and 1.005 specific gravity, with 1.003 being very slightly better but not a statistically significant difference. Color, activity levels, appetite, etc. were also not significantly different either between those two points. Lower or higher specific specific gravity levels shotened lifespan.

All were in tanks with aragonite substrate, so pH and KH levels were stable at each density level.

Is it possible to lower the SG of the F8 if it's in a higher SG?

Yea slowly. Dont shock him with a fast drop in salinity. Just do your weekly regular wc with less salt than you were doing. If your goal is longevity then consistency is your goal. Drop it slowly so he doesn't notice it too much, and keep it at 1.003 once accomplisheds

BW fish can adjust themselves to large SG swings. Bacteria cannot.

Yea, def. don't wanna kill the good bacteria's, and I have pods so will lowering the SG kill them?

Yes, they live in SW. I suggest removing the live rock & sand too or you're going to have a system crash. Might want to start over with a different tank & drip-acclimate the puffer to it.