Ah I have 7 living together in a 30g tank with my big angelicus (syno) my poor lil bullied s.gouramie (He loves the ladies and they look after him, bless. He was bullied by another s.gourmaie until I got him out but his tail has never healed.) some mad danios which may be moving out soon, a baby striped talking cat and a baby peach spot plec. Oh my that tank is full!

Thankfully there will be some moving out when I get my next big tank in.
The last two girls that joined the community were not used to company and flared a fair bit to start with. I honestly thought one may have to be relocated for a short time. As it is, all the girls get on well together. Three in particular are very buddylike.
I can't stress enough the need for them to have plenty of space though. They love the 30g. So much space for swimming and enjoy splatting against the tank back in the current in the extra filter in there. I'd adjusted it so the current didn't flow across the tank and upset them but they go play in it all the time. And they do let themselves get washed into the glass before sitting on the rockwall to sort themselves out. And then go back and do it again!
They do get a varied diet. From the normal betta flake to live bloodworm and brine shrimp. Frequently picking at catfish pellets if angelicus doesn't get there b4 them. Oddly he seems to adore the girls too. He'll happily watch them munch his food, so long as he gets enough and has never tried to hurt them. He's a character too. Gets excited from inside his rock wall when I talk to him alot. Swishes his tail madly.
Ok I'll stop blabbing on now.

)
Yes, that tank is currently overstocked sadly. Not ideal at any time and I'd advise to avoid it. Even when over filtered as mine is. The baby plec and danios will be moving out shortly (For those that tend to worry) and peach (plec) really is still a baby, bless. Like 1" in size baby! Eats well tho.
Enjoy the girls, watch for possible trouble and give them lots of things to keep them interested. Boredom leads to trouble.
Hugs,
P.