Seems to be a very lovely tank, there are just a few things I'd like to point out to you so that down the road you won't be wondering "why did jack the oscar eat jill the angel?".
To start with it appears that the tank is a 55g? It also appears that your stock includes an angel fish, a needle nose fish, 2 oscars, a blood parrot, 5+ cories, a couple african cichlids, some gourami's and a common pleco.
ok now comes the kind of nasty part (I don't intend to be mean in any of my evaluation, but is just my recommendations and some basic knowledge)
First we'll start with the two oscars, oscars are a VERY aggressive fish, they get to be about a foot in length and quite thick, with no other fish in the tank the two of them would require atleast a 100 gallon tank for the two of them. 55 gallons isn't even enough really for one as they are quite a messy fish, and they will kill and/or eat most of the other fish in that tank.
Second is your african cichlids, african cichlids require hard akaline water (high pH among other things) where other tropical fish require softer more acidic waters (expecially your angel fish). So water conditions alone do not make them compatiable with the other tropical fish.
Third, I will admit I'm no expert on needlenose fish, but I am under the impression that they grow to be quite long and are also quite the aggressive fish as well.
My recommendation to you is to decide what kind of tank you want, a community tank of peaceful fish that swim around and enjoy themselves or an aggressive tank with a few aggressive fish that will pick at each other but won't kill each other, or an african cichlid fish tank with african cichlids.
If you decide on a community tank, I would recommend removing the two oscars, the needlenose fish, and the african cichlids. I then would recommend you getting another angelfish, some medium-large tetras (not cardinal or neon tetras), and a couple more of the barbs that you already have one of.
If you decide on the aggressive cichlid tank I would recommend removing ALL of the fish except the two oscars and then upgrading the tank to a larger capacity tank, or removing all of the fish and starting over again with some smaller aggressive cichlids such as convict.
If you decide to go the african cichlid way I would recommend removing all of the fish except the two african cichlids and then check the pH of your water, you'll want it to be about 8.0+ so if it is lower then that I would recommend a crush coral substrate for your tank.
If it was me I'd stick to the community tank you'll have to remove the least amount of fish and it will be the easiest first tank to handle. So your tank would include:
2 gourami
2 angelfish
5+ cories
6+ tetras
3 barbs
1 parrotfish (though I'm not too sure on their temperment so he may have to be removed as well)
o and if that is a common pleco then he'll have to go too as they get to over a foot and a half and a fifty five gallon will be way to small of a tank for him/her. If you want a pleco I would recommend a couple bushnose plecos as they only get about 6" a piece.
Best of luck.
ps- if anyone finds my information misinformative please correct me as I want this person to enjoy their fish to the fullest.