Now I need to decide what kind of fish I want in it. I want a little algie eater for sure. But other then that I am clueless. I have also been sugested some sharks and what not. Now I ask you guys what your suggestions are.

This doesn't count out little lizards btw.

 

vampire plecostomus, or lepard plecostomus, (once you start getting algea buildup)

 

African ciclids purple, yellow, blue are best. prefer brackish water.

 

cyprichromis leptosoma kekese are pretty cool too.

 

Discus are cool too.

 

But, the major thing you need is good lighting, I'd recommend compact flourescents, with actinic and daylite combined. A good filter is critical too. Wet/Dry sumps are best, but a large canister would work for your size tank.

 

If it were me, I'd go saltwater. Its way better, although, you need to take your time. A 20 gallon would be fine for saltwater, as long as you had good filtration. And be sure to buy your fish from a reputible source, that uses uv sterilizers on each tank. Many small stores use UV but, on the whole system, and each time they introduce a sick fish, they put the risk of all their fish getting the same disease. I buy all my stuff from drs fosters and smith online, it costs more for shipping, but its worth it.

 

Great salt water fish include, anything from the red sea, purple tangs are my favorite, but could get a little big in your tank...

 

Percula clown fish. Flame angel fish (good for small tanks). And a couple of goby's (there are some really cool ones, but keep a lid on the tank as they jump).

 

I'd do a mini reef tank, get red/gree/blue mushroom corals first, and elephant ear, easy to manage, and reproduce well.

 

If you want just one fish...

 

Cool ones include cuddlefish, (super amazing color changing abilities, but VERY hard to keep alive, not a starter fish...

 

I had a red volitan lionfish, it was fun to watch him eat goldfish... But, they spit, and he almost burned my house down by spitting onto my powerstrip and catching the whole thing on fire...

 

Light is critical for a reef though. The standard lights won't work.

 

 

 

Here is a pic.

 

When you can keep your those alive for a month, then flush them and buy the fish you really wanted.

 

 

Bright light on top, that generates large amount of heat, will heat up the water during the day, and it will then cool off at night... Your fish will get ick and die.

 

That is why a good light with a temperature variable fan is critical. And a good heater, not the cheapest they carry, but a good one. I run my saltwater tank at 78 degrees. With the heater in the sump filter. My lights are run with a huge fan that keeps the temperature steady.

 

Keep your hands out of the tank. Lotions, and soap are very toxic to fish, especially in a 20 gallon tank. Also, you should let your water filter with no fish in it for about 2 weeks before even attempting to put fish in there. That will let the water cycle. (most people try to rush putting a bunch of fish in, and their levels spike and they die).

 

I've had fish tanks since 1980. One of my side businesses is managing large salt water fishtanks. I've also had a reef saltwater tank since 1994. My first two fish lived until the hurricane this past fall... We lost power for 5 days, and the temperature in the tank got too cold and killed my two original fish that were 14 years old. (the yellow tang in the pic, and the coral beauty in the pic I posted).