Joh wrote:

Dwarf Puffer, Malabar Puffer, and at Big Al,s Pea Puffer

Are these fish Brackish or Not?..... Some sites says they ARE Brackish
and will NOT do well in fresh water, others say they ARE NOT Brackish
but are FULL fresh water fish. Which are they PLEASE?

They are not brackish. They are true freshwater fish.

They will be going into a tank just for them, no other fish.

That's probably a good idea.

The Max size of these fish are around 1.5"?

Mine never got any bigger than about 1/2" to 3/4". I would consider
1.5" their extreme maximum size, and uncommon.

Would a max of 7 be OK in a 20 Gallon Tank?

Yes. I kept four in a 3-gallon tank without any difficulty. You won't
be overcrowding them at all with 7 in a 20. You should aquascape so
they can explore nooks and crannies, and set up territories. Also, I
found that solid background and gravel colors made it easier to see
them. I tried a mixed stone substrate for awhile, and the puffers were
all but invisible against it.

Any and all help greatly appreciated.

One additional note - mine were very finicky eaters, and would only
take frozen blood worms, and whatever extra small live snails I tossed
into their tank. For your own convenience, you should try to train them
to take other foods as well as bloodworm.

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