I have a 10 gallon tank, and i would like to put my white opal betta in the tank i have i have 1 female guppy, 3 neon tetras, 1 black neon tetra, 1 cherry barb but i pulled it out because i read they are fin nippers. I also have a cory catfish and a otocinclus am i okay to put my betta in the tank? PLEASE REPLY
What everyone has said about the importance of shoals, tank size, etc., is true. And great information for future. However, you need to work with what you have at the moment.
With that in mind, if it were my tank and I wanted to add a Betta I would:
Rehome or put the following in another tank: The Cory, the Black Neon Tetra and the Cherry Barb. Then I would get five more Oto and five more Neons. Watch closely and if there is any sign of nipping by the Neons I would move my Betta.
When determining how many shoals there can be in a smaller tank note whether the inhabitants are bottom, mid or top dwellers. The Oto are bottom, Neons are mid and Betta top. Filtration is important, too. Do you know what's your filter? You just might need to go up; but maybe not.
Planting the tank as heavily as you can with live or silk plants will help, too. Perhaps, at some time in the future, you can get a 20 long tank (my favorite size). That would allow you to add to your current shoals or introduce more species.