my first piece of advice go as big as you can afford, this is for 2 reasons...
1: this hobby is highly addictive
2: the larger the tank, once "started" the more stable the tank and the less liley you are to loose everything should your paameters fluctuate...
(ie 1 drop of chlorine in 1 gallon vs 1 drop of chlorine in 100 gallons...)
second, look into fishless cycling...its the ost cost effective, kind (fish are ot sacrificial) and effective metod of starting your tank, if you've got frineds with tanks ask for some of their gravel and put it in your tank (or filter) to help "seed"
and BE PATIENT when cycling, its all too tepting to look at aigempty bo of waterand want to add your fish, but test test test and don't rush..youl be glad you waited.
3rd, when adding fish, go slow, when you have a stocking plan, start with the hardiest species on the list, and add no more than a few at a time. agai this goes back to the 1 drop making big changes, the more fish you add at once the oreit will effect your ammonia, nitrate, and nitrite levels thus essentially starting a new mini cycle, if you add a lot of fish all at once youll risk throwing your balance way out of whack and essentially starting fro scratch.
now that being said, in terms of what fish to get...
1: do your homework...you wnt to stock your tank based on the fishes ADULT size, and compatibility...
do you have a "theme" in mind...them could be "I want it simple" or "lots of color" to "id like it to look lika an amazon jugle" or "peacefull"
perhaps youv been to a fish store and seen a type of fish you just would LOVE to have and want to base your tank around that fish?
liveaquaria.com is a good place to get some ideas of the ore common fish available in the pet industry....I wouldn't order from them...but it s a good place to go to see pictures to see "ooo I realy like that one" from there we can easily help plan your tank.
general rule of thumb, for tropical fish 1 inch of ADULT sied fish per 1 gallon...
for cold water fish (goldfish, koi ect) 10 gallons per goldfish is about your bare minimum.
and "zone" your tank...
ideally you want fish that inhabit different zones of the tank...
bottom dwellers like corydora, shrimp, pleco and cats/sharks (pleasenot most pleco and cats/sharks are NOT suitable for tanksunder 55gallons, there are soe dwarf species of pleco that will do ok in 10-20 gals but generally they are special order)
the theres the midground, typically schooling fish like barbs, tetras and rasbora occupy this area since this tends to be the eyes focal zone this is typically where people want their "flash"
then theres the top, this tends to be home of the goramis, livebearers like guppy and molly and the danios.
for me the goal of the tank is to have activity in all zones, but to also balance that activity...
for example in my tank I have angelfish who primarily occupy the upper to mid level...these guys are south American cichlids, and WILL eat anything that fits in their mouth if not kept well fed., because of their tendency towards being territorial and occaisonaly aggressive I decided to leave the top level primarily as their territory, with plenty of tall broadleafed plants to caim as hiding/territory.
for my middeground I whent with a LARGE group of neon tetras, in the wild the neon is the angel fish's natural prey..my angels are ept VERY well fed and after 2 years weve had no incidents (and yes my angels are adults) Because I love the neon so much I decided to primarily focus on them as the middle ground fish, they are flashy and active and do best in arge groups anyway...
for my bottome dwellers I whent with another favorite, julli corydora, and again becaue these little clowns like to live in larger groups I dedicated the bottom of the tank pretty much to them and got a nice sied group.
oce my tank started growing algea I also added a group of ottos, tiny little algea eaters who are amazing! they go anywhere the algea is...
hope that give you an idea
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