okay here goes (still nursing the evil slap from the very evil one cm) just hope that i do not come off looking like danny but i think my worst fears are about to be realized! oh well, make him proud then.....
first of all gad is right. way too many fish for the tank. maybe if you had the 160 gallon tank.
second, some of these fish may have problems with some of the other fish. not the peaceful community that you may be looking for. going over each one individually you may see some of the problems that you may have.
hatchetfish they like to have schools of 5 or more. they like to have faster moving water so one area of the tank will have to have an adequate current. may find they are hanging around your powerhead and filter to acheive this. they like to eat live foods, get to be around 1 1/2", temps of 72-80 degrees and ph of 5.5 -7.5.
downfall : with a school of 5 @ 1 1/2" you have 7 1/2" of fish.
elephant nose 2-4 will result in one becoming a bully and very aggressive. a school of 6 or better is recommended to keep the aggression levels tolerable. like temps of 78-82. each will need their own cave or hidey hole. they like live foods and are notorious escape artists. also get to be 9" in the aquarium even though some in the wild grow to lengths of 12".
downfall: 6 @ 9" is 54" of fish. unless you want to use this tank as a grow out and transfer them when they start to get to be matured. seeing as they need their own hidey hole or cave the footprint (bottom surface area) may not work well with this fish. they would do better in a longer tank, more footprint. also will have to make sure that the entire top of the tank is covered with no holes for escape routes. would be good in a drilled tank.
cameroon armoured shrimp like the cooler temps of 71-77 degrees, ph of 6.5. they do need to feel safe in their environment where they will not be considered food. grow to be about 2".
downfall: may be considered food by some of the other fish, especially the gouramis.
tetra tetras are characins. the most notorious of the characin is the pirranha. even though when properly fed you can put your hand in their tanks without getting bitten. bad rep but that is another post. they like temps of 78 and ph of 6.5-7.0. they are found in darker waters so they do need an area of darkkness. cardinals get to be about 2" and rosys abut 2 1/2".
downfall: may have to reconsider the lighting or create a darker area in the tank for them to feel comfortable. again the footprint is the problem. 10 cardinals @2" is 20" of fish. 6 rosys @ 2 1/2" 15" of fish. characins are notorious plant eaters. the pacu is a perfect example. the tougher plants will be ignored, but the swords and valisneria may get the brunt of their abuse. even though characins are omniverous they will take the opportunity to pick on weaker or injured fish. they also have teeth and may eat the shrimp especially.
pencilfish also a characin. get up to lengths of 3". temps of 78 and ph of 6.5-7.0.
downfall: 4 @ 3" is 12" of fish. also it is a characin.
catfish they prefer ph of 6.5 - 7.8 and temps of 77-82. the leopard will get to lengths of 1 1/2" and the bronze 2 3/4".
downfall: the leopard requires fine sand or very small stones to avoid injuring their barbs (whiskers). 6 leopards @ 1 1/2" is 9" and the bronze @ 2 3/4" is 16 1/2" of fish. also would have to limit your substrate to sand or fine gravel.
half banded koolie loach they are nocturnal. like to bury themselves in sand during the day and come out to feed at night. they prefer live foods, get to lenghts of 4", prefer ph of 5.5-6.5, and temps of 77-86.
downfall: may have problems with the plants staying rooted. would also be limited to sand as a substrate. since they are nocturnal may have problems with the lighting and ensuring there is food on the bottom for them to feed on at night. you do have some daytime bottom feeders. also 4 @ 4" is 16" of fish.
checker barb grow to lengths of 2", like temps of 68-84 and ph of 6-6.5. also need a school of 6 or better to feel comfortable. when fed live foods it conditions them to spawn. the male will get redder in color and the female will turn white.
downfall: 6 @ 2" is 12" of fish. when feeding live foods to the others that require it, you may induce them to spawn. not a really big problem but the fry may become lunch for the other fish.
pearl gourami will at flake food but when fed live foods are conditioned to spawn. they are bubblenest breeders and the male will become very aggressive protecting the nest. the males when matured will display a red throat. they prefer temps of 75-82 and ph of 6.5-8.5. can reach lengths of 5".
downfall: bubble nest breeders make their nests at the top of the tank. if they do spawn, they may consider their nests being threatened by the fish that prefer the top of the tank. they will kill or be killed protecting their young and will become very aggressive. also live food conditions them to spawn, if you do get two males then they will fight with eachother when conditioned.
harlequin they prefer schools of 8 or more, reach lengths of 2", prefer temps of 72-80 and ph of 5.5-7.5. they like live foods especially small crustaceans.
down fall: whatch out shrimps!
also 8 @ 2" is 16" of fish.
zebra danios they like temps of 64-77, ph of 6.5-7.2, prefer schools of 6 or more and grow to lengths of 2 1/2".
downfall: 6 @ 2 1/2" is 15" of fish.
so now you have 207" of fish. you would have to maintain a ph of 6.5 to 7.0. maintaining the higher ph of 7.0 you would lose the shrimp, maintaining the lower ph of 6.5 you would lose the tetras. temp would have to be around 78 kinda iffy for again the tetras and the danios.
substrate would have to be sand or you would lose the leopard cat and the loaches. also with the amount of sand required to have the loaches bury themselves, you now lose some of the volume of water like gadazobe pointed out.
the tank would have to be totally closed so the elephants would not escape. don't want to have a bunch of elephants running lose in your house!
alright bad joke.
not even going to try with the plants that is rose's area of expertise. with the characins you will have to be careful as to what plants you chose. my pacu eats everything in site. even though i was told that he is peaceful and non aggressive he has eaten other fish. so that is a fallacy.
got to stop rambling! going to grow a mustache like danny in a minute! yeesh!
hth
maggie
edit to make the bold work
yep it it 
/www.littlefishtank.com/utils/calculator.asp
