What are the chances of my fish being compatible

[Xr3]

As of right now I have a 10 gallon tank with a bunch of tetras a few corys a betta and a adf and everyone is happy and all is well. The betta does not attack anyone nor does he chase anyone he simply goes about his business and leaves everyone alone. I also have a 40 gallon tank that has been cycling for over a month now in all about a week ago I changed the gravel from a really sandy type to a bigger type of gravel and all my water levels are fine. 8 days after the new gravel I added a blue gourami and he is doing really well along with my water levels (I have been using some starting chemicals to help with the positive bacteria)
My question lies with whether I could get an angelfish and a rainbow shark together. I have asked around and also talked to my lps and everyone so far has said yes so Im also wondering if I could have a few bettas in there.. Sorry for such a long thread just wanted to explain my situation.

 

[nirbhao]

Neither of your tanks are big enough for a rainbow shark. Multiple bettas, especially with gourami, could be an issue.

 

[Delapool]

I'd be wary on several bettas and gourami as well.

Angelfish and betta I've kept together fine but don't know if that is normal (might have been those fish).

The main issue I've found is the betta deciding to box out of his weight division.

 

[Xr3]

I'd be wary on several bettas and gourami as well.

Angelfish and betta I've kept together fine but don't know if that is normal (might have been those fish).

The main issue I've found is the betta deciding to box out of his weight division.

I believe that I'm just going to get the angel fish keep the gourami and have the rainbow shark until he outgrows it and swap him to a 55 down the road.

 

[e.mmareese]

I wouldn't have a betta with an angel in my opinion, I've never had them together or tried to but at my LFS there is a tank with a betta and a few angels and the angels chase the betta and nip at its tails and i always feel bad for him[emoji28] but as for the rainbow shark and angelfish they would be fine together just make sure you would have 1 or 4+ angels, I would go with 4+ just so its not alone and they would benefit eachother/act more normal with the others, good luck!

 

[GuppyGuy333]

multiple male bettas? NO NO NO
multiple female bettas are risky.
one male betta in a community tank can be a gamble. some bettas are more aggresive than others.
i have read that gouramis and bettas can work but also might not
angels can be aggresive and territorial so it could also be a gamble having one with one male betta.
"sharks" can get huge and outgrow your tank.

 

[Xr3]

multiple male bettas? NO NO NO
multiple female bettas are risky.
one male betta in a community tank can be a gamble. some bettas are more aggresive than others.
i have read that gouramis and bettas can work but also might not
angels can be aggresive and territorial so it could also be a gamble having one with one male betta.
"sharks" can get huge and outgrow your tank.

I have a 55g tank and my lps can take him in it something goes wrong with the 55 I'll be setting up soon. (the shark that is)