I've had my Dwarf puffer for only 18 hours, but i want to make sure that my home for him is as hospitable as possible. He has been glass surfing since i got him yesterday, but he does wander around the tank some, but i am still a little concerned.
currently, my tank holds 6.5 gallons of water.
stats:
PH - 7.6
NH - 0
NO2 - 0
NO3 - 0
GH - 9.8
79 degrees water
I dose 1mL flourish ever 3rd day, and .5 mL carbon twice a week.
he doesn't have fish tank mates, but there are 4 ghost shrimp which he is currently ignoring, except when he runs into them while surfing, around 20 or so trumpet snails, a handful of pond snails and decorations:

Video of his pacing:

he has 3 caves - one under the slate and 2 under the drift wood. as you can see there are a lot of plants and rocks, i feel like he has plenty of hiding places. I upped the water speed a little when i saw him swimming up the current, but any farther and my pump will out pull my return water.
Am i being paranoid? any suggestions on what i could add?