Puffer Fish??

Question
Hi,
  I am new to the whole aquarium thing. I found a 50 gallon tank on the side of the road and decided to clean it up. I wanted saltwater (I love the ocean) but after researching, I decided that freshwater would fit my schedule better. I let it cycle for 2 months and then got fish. I have gravel, many fake plants and 1 real plant (I do not know what kind) with 3 houses, a 250 watt heater, 2 filters (Aquaon and Tetra) and a bubbler. I also put in some aquarium salt for electrolytes. (is that how you spell it?) I currently have 9 platys, 2 black skirt tetras, 2 albino cory cats, 2 fiddler crabs, 1 aquatic albino african dwarf frog, 1 aquatic african frog, 1 chinese algae eater, 1 freshwater clam, and 1 tadpole. My tadpole is just a huge tadpole that I got from a friend. I know that black skirt tetras and cory cats should be in bigger shoals but I didn't want to cram the bioload too quick. They are part of my platy pack, as I call them, and seem to be doing fine. Everybody is very healthy and happy. (They even sleep in a huge pile together.) Should I get more of them, or would that would be cramming it? But the whole reason I am writing this is about puffer fish. When I first got my tank and wanted saltwater, I wanted a puffer fish. But things changed and life moved on. Just today I was at petsupermarket buying my plant when I saw a spotted puffer fish in a freshwater tank! I asked the guy if he would be OK in my tank but the worker said he didn't know. (Of course) Petsupermarket have a colour coded system: mean fish with a red dot, semi-mean with a yellow, and easy going with a green. The puffer fish had a yellow dot but was mixed in with green dotted fish. So will he be OK in my tank? I feed them Tetra flakes twice a day and frozen bloodworms on the weekends. But if I did get a puffer, would that be too many fish squished in my tank? He would be the last fish for sure. I am just scared of the happy environment going away. I do 10-20% water changes every weekend and clean half of my gravel at that time. I keep the temperature at 24 c (76 f) and a PH of 7.4  .   I have 2 pregnant fish that should be due any day know. If I can get a puffer, do they need any special requirements? Thank you very much!

Answer
Hi Megan,
 I strongly suggest that you not get that puffer!  Puffers are really cool fish but they are also very determined and effective predators on other fish, including pretty much all of the fish that you currently have.  Puffers look slow but they can swim very fast. They are very smart and they will hunt down and eat your other fish, one by one.

-- Ron Coleman
  rcoleman@cichlidresearch.com
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