pimp my fish tank?

You actually don't need gravel. You can add gravel if you want but adding gravel will just make the tank more difficult to clean. It is easier to siphon waste out of a tank with a bare bottom. I would not recommend live plants because the bulbs that come with most tanks (if your tank even has a bulb) will not be enough to keep a live plant alive. Plastic plants (maybe siliconed to a small rock to keep them down) would be more appropriate.

If the tank has filtration your Betta will be happier. Also, you should check into one of the tiny heaters made for small tanks. Bettas really do much better and live longer at warmer temps (around 78 degrees F) than at room temp.

Your Betta's fins will likely not grow longer if it is close to adult size. The only exception would be if it is recovering from damage due to other fish nipping the fins or disease. Then the fins would grow back but probably not as long as they once were. It sounds as if you have a female Betta. By the way, I would not put anymore fish in there with the Betta. If you do you will be overcrowding and find it hard to maintain water quality.

A 2.5 gallon is a great environment for a betta assuming the kit contains a filter and a heater.

Decor of course is so much a matter of personal taste byt I have found that fish seem to do much better over a darker colored gravel. They seem much less nervous and stressed that way. Personally I prefer it too, it just seems to look more natural. Past that I say let the kids pick a plant or orniment each that they like. Just something small so it doesn't crowd the fish.

MM

It's not really worth buying a small tank like that at their general price unless you don't have enough space for a larger tank. I would get a ten gallon tank. I bought one for my hamster recently and it only cost me eight dollars in petland discounts. If you were to get this tank you can put a few plants in it. I would recommend putting 1 plant in your small tank. About it's fins, when you bought it, do you recall it being a female, male, or crowntail? Females have short fins that remain short hence why they are cheaper. The males have longer fins. Crowntails just have fins that end in points. If it's a male and it has short fins,then it may just be young, but it's doubtful. You can also put any kind of small cave in there for him to hide in. If you want plants that aren't green, just get some of those pearl colored plants. I prefer natural colored artificial plants but whatever floats your boat. Don't get any live plants. They wouldn't survive in a small tank and without good lighting. Make sure you condition the water and do water changes every week or so and good luck to you.

is the tank unfiltered? in which case, get either a thin layer of coloured marbles, or larger rocks for the bottom of the tank rather than fine gravel, this means when you clean out the tank you can take these out and get the poopy much easier than if it was mixed into lots of fine gravel!

i would recommend a silk plant rather than live, live plants can be hardwork to maintain, especially if the tank has inadequate lighting and isn't filtered. whereas silk plants can be taken out during water changes, wiped clean, plopped back in, and won't cause any damage to your bettas fins!

avoid anything with sharp edges, such as plastic plants, or anything from around the home, be wary of what you put in, just in case it leeches anything into the tank.

maybe have some nice biggish rocks (get from a fish store or advised from a fish store, some types of rocks are safe such as granite and slate, some cause problems such as quartz and chalky rocks) or marbles, a little terricotta (unpainted) pot with the whole sealed up (i've heard horror stories of fish getting stuck in that hole and dying!) for him to hide in, and a silk plant to rest his butt on.

he'll need cleaning out at least once a week, about a 50%-70% water change for an unfiltered tank. dechlorinate the new water and make sure it's at least room temperature before replacing.