[frankiefire]

I have a six gallon heavily planted column tank. It's a six gallon. It currently has 3 ghost shrimp and 1 pea puffer. My question is can I add another puffer? If not are there any small fish I can add? Thanks in advance.

 

[BWG]

No to both questions. Dwarf puffers don't mix well with other species due to their aggressiveness and do best in species tanks. Same thing with each other. While it is possible to keep more than one, you need space and you're not going to have that in a 6 gallon aquarium. I wouldn't be surprised if your ghost shrimp became food.