27G - I had previous experience from 20 years before so started sensibly with tetras, live bearers, corys etc but soon started over stocking dramatically trading guppies and replacing with Angelfish etc, bought another 20 gallon to put some in etc.
3 biggest mistake buys which the books and internet sites got wrong were;
Badis - only eat live food so ended up wiping out about 3 small cardinals and 6 small hatchets within a week or so, for something to eat.
SA Bumblebee Catfish - It really is a freak of nature what they can fit in their mouth.
Female Siamese Fighter - I had 3 in a community peaceful set up and one went berserk, killing Neons,lemon tetras and a variety of others.
My original tank from 1988 when I was 13 started with (as recommended by the LFS
) 3 Tiger Barbs, 2 Angelfish, 2 Firemouths, 2 Bala Shark. This is a tank of roughly 40 gallons. I still occasionally use the place, it's the same guy too but I rarely ask his opinion, funnily enough!
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