Looking For Two Different Sized Fish For A Tiny Tank

[Revision17]

So, I have a friend who now has a "little sister" in her sorority. As per their quasi tradition, she's going to get her little sister a fish tank with a big fish and a smaller fish (big sister and little sister). However, this wasn't planned very far in advance, and she's going to want to give the tank to her little sister Thursday (nov 1), so there won't be really any time to cycle the tank.

I do have lots of Dwarf Sagittaria in my tank (they multiply like.. grass). Maybe it would help with doing a "planted cycle" as per this page. I haven't heard specifically about cycling a tank by using tons of plants to act as an ammonia buffer, but it seems like it could work.

The tank will be in the 1.5-2.5 gallon region (one of those kits with heater, filter, and light).

I'm stumped as to the type(s) of fish to put into it. The following criteria have to be met:

• Hearty against ammonia and nitrites (since the tank won't be cycled). Rules out little tetras.
• One fish must be larger than the other. Oh, and they must be fish, no snails or shrimp.
• Fit in a 1.5 to 2.5 gallon tank. Rules out danios.
• Readily available from most fish stores. Rules out Endler's Livebearer.
• She doesn't want to have large betta and small betta with a divider between them. The fish should be chill together.
• She thinks catfish are ugly, especially the super cute corydoras (well pygmy cories probably wouldn't survive the cycle anyways).

The only thing I can think of are maybe guppies. Though fancy guppies IME aren't super hearty for the cycle (tank is a bit small too). Petco feeder guppies are probably diseased. Maybe two barbs of some sort (probably tiger, since they're usually what's available)?

Any ideas? If nobody can come up with a solid plan, she'll probably end up getting a big goldfish and a little goldfish.

 

[shroob]

If you or someone you know already has a fish tank, you could possibly lend some media, as with this there will be no need for a cycle.

The tank is rather small for fish imo, if you can go bigger, so much the better. The only things I can think of is oto's, and they like to be in groups so Im not even sure on them.

 

[eschaton]

Sounds like a world of bad choices, but I don't want to consign goldfish to this tank, as that would be torture. Tiger barbs are a terrible option too, as they get pretty large and pester each other in groups of less than 6. All of these are bad options, but they might work.

1. Female Betta/Male Guppy
2. Female Platy/Male Guppy
3. Female Betta/White Cloud Mountain Minnow
4. Female Platy/Pygmy Gourami
5 Dwarf Puffer/Bumblebee Goby
6. Killifish of some sort/any of the smaller fish listed above.