Puffer question

[pinkpufferfish]

Well I love my F8, and I have had him for quite some time. Anyway, I just moved him to a larger tank a 20 + gallon( I said 20+ because I am still unclear how many gallons it really is, but it's not over 30 that's for sure) anyway, he's with his usual friends my yellow lab, two clown loaches, and 2 plecos and he enjoys it. However, he is always doing the "up and down" swimming that is so common with puffers. From reading around, I know that the "up and down" motion is not a good sign, he's not sick (at least I don't think so, he eats well, swims around happily) doesn't have Ick or anything of that sort but it still worries me. I tried putting in a plant to see if it would stimulate his interest, and he does look at it curiously, and I find him down by the plant sometimes, but most of the time his favorite thing to do is to follow me around and do that "up and down" motion. I am planning on heavily planting the tank to see if that works, maybe putting in a few snails for him to hunt too. If that doesn't work, then I am going to conclude that he may be sick. So, what does everyone think? Does he just need "more to do" or is it an actual problem. Oh water conditions and PH is fine. And, okay, okay he is not in a brackish environment just yet. I am trying to determine if my other fish can handle that, and at this current time all arrows are pointing to no they can't so I could be answering my own question but would like some advice if I can. Still kind of new to puffer handling.

 

[SirMinion]

The up & down motion is usually indicitive of stress and the puffer's attempts to swim away from the cause of the torment.
In this case it's possible that he's attempting to migrate away from the freshwater in the tank in search of saltier evirons.
Time to move him to brackish.

Your other fish, especially the plecos & loaches would suffer greatly with the addition of salt, and the amount required to keep the puffer happy will possibly kill them quickly.
Time to buy a new tank too...

 

[Pufferpunk]

You are combining FW & BW fish in the same tank, wich is a very bad idea. F8s prefer a SG (specific gravity, a measurement of salt, using a hydrometer) of around 1.005. To acheive this, it takes around a cup of marine salt/5gal (rough estimate).

Please read: Figure 8 Puffers