I prefer undergravel filters , 2 ( 1 pair / tank ) ; when dirty , simply put siphon hose assembly ( plastic pipe , thin wall with plastic hose ) over discharge tube , start siphon , and will suck out contents of filter ( black molases like sludge ). I also have a exterior power filter in conjunction with undergravel filters .
Remeber that fish feed at a certain level in the tank , and once the food falls below that level will not move up or down to feed at different level ( unless hungry )
ie: top feeders .... guppies , mollies , platys , betas , gourami's
middle feeders : tetra's , zebras ,
bottom feeders : catfish , loaches , snails
Stay away from members of cichlid family at first , aggressive , and will eat smaller fish : angels , oscars , fire mouth , jack dempsy , cichlids .....
1. Basic need : heater specific for that size tank ; air pump , valve assembly ( gang valve with 4-6 ports ) ; air stone ; filter(s) corner , bottom , exterior (as desire) ; gravel in tank 1-2" thick ; hood (cover) and light ; plants [ valisenaria , myrofillium good ]
2. clean tank walls with sponge and a little table salt ( to remove dried up food / algae ) , rinse tank ;
if wish to try undergravel filters place in bottom of tank with air tubes in corners , cover with stone ;
if desire to use corner filters , place stone in now ; fill tank about 1/3 full of water ( any leaks ? ) let set for 1-2hrs ;
fill 1/2 full plant plants , add decorations , place large bowl in center in bottom ( so once set up and add additional water , bowl will prevent disturbing " good stuff " if pour water into tank , into bowl )
hook up air pump , connect to filter , air stone , etc. and adjust valves to get
slow gentle flow to filters ( if have 1 more valve than devices , can blow extra air out into room , and cut back as pump ages and lime builds up in air tubes )
hook up heater , check pH of water ( want to be about 6.8 )
let tank warm up to 68-72 degrees ( may take a day + ) depending on tank size
do some window shopping , ask questions , look for ideas .....
find some one who has tanks , go over for a cup of coffee , look , make sketch ,
ask dumb questions [ they might come over and help you set up tank... ]
go shopping for critters .... start with 3-4 midsize fish [ ask people at pet store if ones you like , will work together , otherwise may have a expensive 10 minute show and funerals when add them to tank ....and a couple of catfish ( corydors ) for the first month --- build up bacteria , allow tank to stabilize ,
see how fish do together