My favorite fish?
Striped Kuhli loaches, even when they hide a lot.
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This is Big Bertha, in my 29g.
And my Chocolate Kuhlis!
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I have six in my 15g, along with an increasing number of Red Cherry shrimp.
I love Cory cats, too, but since I already have loaches as my bottom feeders, adding more just means someone is going to be hungry.
I also adore Zebra danios, the cheapest fish in the LFS. When I was still young my middle/older sister bought herself a 10g aquarium. The heater malfunctioned and it was about 110°F in the tank. All her fish died,
except the Zebra danios. Love 'em!
Bettas are nice, but I especially love the coloring of the females. Some day I may have a girls only tank.
My 29g is kind of empty right now. Aside from a few Kuhlis about 3 years ago the last time I added fish was in 2016. Yep, 7 years ago. The remaining residents are 6+/- Kuhlis, one Zebra danio, and 2 Glowlight tetras (NOT Glofish). I want to add a shoaling fish, and have chosen Ember tetras:
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They don't grow larger than 1" so I can have a bunch of them in either my 29g or 15g. I just placed an order online. They'll be shipped next week!
And I also ordered 4 Nerite snails. They're powerhouse for algae control.
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Olive Nerite on the left, spotted Nerite on the right.