What do freshwater exotic fish need?

First, you will have to cycle your fish tank before adding any fish, or they will die. Please read this article:

Second you’ll need a filter, gravel, and lights. You’ll also need a heater and thermometer.

Good fish for a 20g are tetras, corydoras catfish, small plecos, bolivian rams, dwarf gouramis, platies, guppies, mollys, etc. I suggest you look at the fish on aquahobby.com and ask on the forums which would suit your setup best.

If all you have is the tank, you’ll need a lid.
You can get a glass lid for 10-20$, and a light fixture for another 30$ or so. Try to get a fluorescent fixture if you can, that way you can have plants.

You will also need a filter. I suggest you get an Aqua Clear 50…. Get a hang off the back filter, rated for at least 20 gallons MORE (so get a filter for 40 gallons)

You will need some gravel. You can get a large bag for 15$. I suggest you get small smooth gravel, not big chunky gravel. I prefer natural colours, but that’s just me.

You’ll need a heater, get 75Watts, make sure its subermisble. Ego-Jagger is a good brand. 15-25$ (don’t skimp on the heater)

You’ll need various decor. Personally, I prefer the natural stuff, like driftwood (1-10$), rocks like lava rock and texas holey rock (1-10$) and real plants (1-10$ each). Or you can go with the fancy castles and fake plants (1-20$)

You will need dechlorinator to neutralize the chlorine in your tap water (5-10$)

You will need a vacuum tube to clean your water and vacuum your gravel - you should change about 20-30% of your water every week (5-10$)

You should get a fishnet (2$)

You should get some Bio-Spira to cycle your tank (5-10$)
*This is VERY important

And then you’ll need the fish.

In your 20 gal, I would suggest you get a school of 10 tetras (see my response to your other post) (1-3$ each)
A school of 6 corydoras (1-6$ each)
And a dwarf gourami (5$) OR a pair of bolivian rams (5-10$)

Try not to overstock.

You’ll need fishfood, of course.

One way to save money is to buy used. Try craigslist.com , fishforums.com or your local aquarists society. The only thing I don’t suggest you buy used, is a heater and a filter. But you can find fish, plants, fishfood, tank decor, light fixtures and bulbs, etc, for low prices.

Good luck!

Definitely cycle first. You must be patient, as it can take anywhere from 2 weeks to over a month. Buy your test kits. Basic ammonia and nitrite kits cost less than $10 each.

Most people will recommend that you do a fish-less cycle, using household ammonia (with no surfactants) with a eye-dropper. There are variations in this method, so you can look it up on-line.

I recommend mollies, guppies, and platties.

Get readings of 0ppm first, though.

Caring for these exotic types is very pricey they need food to live and other objects to hide from predators snakes, oscars, pirahnnaas etc……