well, let me first say a shrimp tank is a wonderful idea thats easy to care for and looks very intresting.
a 5 gallons is big enough for colonie of shrimps.in a 5 gallon i would say the amount of shrimp that could be kept is app. 10-15. some people may say more, but i like to give them planty of space to move.glass/ghost shrimp are probally the most common, amano/algea eating is also readly avaiable.ive heard ghost shrimps will eat other shrimp, but ive never had any problems. ive kept ghost and amano shrimp together and all has been well. i dont know much about other species such as red cherry shrimp or bamboo, but heres a useful website:http
/www.petshrimp.com/
any aquatic plants will be welcomed by the shrimps, java moss and moss balls are their favourites, IMO. but give them a varitety of plants, such as broad leaf ones and tall wavy plants. a nice piece of bogwood would look nice, most aquatic woods will look good and the shrimps like to crawl all over it.caves are good as shrimps like to hide when scared. again, rocks are also welcomed to crawl over and give them more than just a flat substrate. speaking of which, gravel or sand is fine. sand is probally better and easier to feed them. a thin layer of gravel with a thicker layer of sand on top is a good choice, the plants will grow better. alternativily, cover half the tank with sand and the other half with gravel to give the shrimps as choice.plus i think it will look cool with 2 substrates.a heater is nessery as most shrimps are tropical and i always use a filter. a simple filter will do, make sure it doesnt move the water too much and it wont suck up any shrimplets or shrimp legs. again, a simple heater will do. there are plenty of heaters to choose from for a 5 gallon. a light is also important, not only for the plants, but i think to mimick the natural day and night formations that happen in the wild.it also produces some algea which the shrimps feed off. a cover is a must. shrimp do jump and will jump if a cover is not provided. i think the tank will have to be cycled first. even tho shrimps dont produce much waste, a uncycled tank might kill them.i would treat the shrimps like fish, needing regular water changes with treated tap water, regular feeding, and pretty much the same care, is a shrimp dies, i would leave it in for a bit, as other shrimps might eat it and gain nutrients and other good stuff from the dead body.of course remove it after a while.be prepeared to see lots of old skin as shrimps moult.they will either eat this old skin or remove it.to feed them, a shrimp pellet will do, but bloodworms are enjoyed and so are algea. most fish foods will be eaten like flakes.
i cant think of anything else, if i do i will post it.
good luck
I love my amano shrimp. They're fantastic to watch and surprisingly charismatic. I'd recommend them to any beginner, as they're quite tolerant and easy to care for. Oh, but I think the filter depends on your shrimp. Mine quite like riding the water currents. 
