Your water temp is too low which may be causing stress on your bettas and thus they're falling prey to bacterial or fungal infections. Bettas really do prefer warmer temps at about 78-82 degrees F.

What you may want to consider if you're going up in size is a 5 gallon with a plastic divider to keep them separate. Then you can also get a 25 watt heater to keep the water temp where it should be. Get a small aquaclear or marineland filter and it'll do better at filtering the water than what you'll get in a 2.5 gallon tank with one of those undergravel filter systems.

Many times with bettas, water changes every other day will clear up some issues. Even with spring water, you should still be using a water conditioner, btw. And you don't really HAVE to use spring water unless your water is so bad you're not drinking it from the tap. You can simply fill up a gallon jug, let that sit for a couple of days to let the chlorine disappate, and treat for chloromine (unless you know your water content, it's better to treat than not treat).

Loss of colour could be from a bacterial infection. Clamped fins can also mean a bacterial infection. Clamped fins is a general sign of stress - which could be from an infection (bacterial or fungal or parasites)

Don't treat unless you know for sure what is wrong with your betta. Be careful when using salt with bettas - because they're housed in such small containers, there's a tendency to overdose on the salt.

For fungal infections, I usually use Fungus Cure (I think by Jungle?) which contains malachite green. Malachite green always seems to work well for me when it comes to fungal diseases.

A half-gallon tank needs a full change every 3 days. The older your fish get the more easily bad conditions will wear on them. Between the low temperatures and the questionable water it's no wonder that your fish look worn.

Real fungus, saprolegnia, will not attack unless there has been some kind of trauma to the flesh. That does include fin and body rot. Columnaris, known as false fungus or cotton mouth disease, attacks in poor water conditions when the water is too cold. If you are seeing white fuzzy things that grow on the fish and then detach and disappear/waft around the tank, that's a sign of columnaris. Treat with Jungle Fungus Clear or Eliminator in a 1 gallon+ hospital tank with an airstone set to low and temperature at 76 degrees.

Once your fish are better and in larger tanks (2.5 gallon is fine) raise the temperature to 78-80 degrees.

Just a thought about housing the 2 bettas. A 10 gallon kit with a tank, hood/lighting, filtration, and heater is

Ok, thanks for all the help. I got a 5 gallon tank with divider, a 25 watt heater, and a small filtration system. They don't have a fungus, just color loss. Should I put them in the new aquarium and see if this helps the situation or should I do something about the possible bacterial infection before I put them in a system where water will flow freely between the two fish. Also how often do I need to change the water now that I have the 5 gallon tank?

If both fish need to be treated for the same disease then putting them in the seperated 5Gal. is OK. If you are only treating 1 fish then leave that one in its original bowl. I wouldn't treat the fish with any medications until you can be sure they have an infection. More often than not just improving the water quality is the best cure. Sadly some times it is too late. If you don't allready have one an ammonia test kit would be money better spent than medication. A complete set is even better. One that tests for ammonia, nitrite,pH and nitrate is ideal. The reagent type (chemical and test tube) are usually a little more pricey initialy, but they last up to and over a year. Test strips are sometimes less expensive for a few tests but a years worth will be way more$$. At first you will need to test your water daily until the tank is established, there after once a week with a 20%-25% water change ( can take 1-3+ months). This is if you deside to cycle the tank of course. You can treat the tank like a bowl and just change the water also. The heat should be an improvment and encourage the 1 betta to eat. Also some medications will stall a new system trying to establish, or kill an exixting one (some medications state they do not harm the bio-filter, but they have like maracyn2, on the other hand maracyn1 indicates that it will hurt the bio-filter and in some cases hasn't). I guess the best thing to do is start the new tank like you aren't going to medicate. If you need to medicate 1 of the fish then remove it to a bowl to treat it. There are many articles on the web that explain the nitrogen cycle in detail. I would do a yahoo search and go with one that is easy enough to understand. Some are written so a bio-chemist would be confused.

If you think there isn't enough water flow, punch more holes in the plastic divider. I've seen in some LSFs where they actually use plastic grids as dividers to allow for better water flow between sides.

With the 5 gallon I'd still do weekly water changes. And as they are not doing well, to do this bi-weekly won't hurt. You'll have to expect that the filter has not established any good bacteria yet, so you definitely want to be doing water changes (at least 25%) twice weekly to address any ammonia issues.

Unfortunately, bettas are not always in the best of health when we get them. So don't assume that they became ill solely under your care.

Quite honestly, I think the warmer water will help. the temps you were stating in the beginning are more goldfish temps than tropical or betta temps.

Thanks for all the help. I can already tell the difference in the fish. Yusuke, who had his fins clamped before, has unclamped his fins and is siwmming around more. And they started facing off, or showing off, or whatever you want to call it again. Guess I should have researched bettas a little better before I got them a couple of weeks ago. Thanks again.

I agree with more frequent water changes. The smaller the system the more suseptible it is to sudden change or toxic spikes. One thing I forgot to add on that note. If you use spring water uncover it a day or two before use or aerate it with an airstone and pump. The reason is most spring water builds up CO2 when it is stored in a bottle without any oxygen. CO2 (carbonic acid) will make the water very acidic, usually less than an aquarium pH test set can measure. Once the water is aerated the pH will soar to its actual pH. Most spring water is base 7.8ppm pH>. The concern with this is the water in the aquarium will fluctuate pH drasticly when doing water changes. This is also a stressor to fish. This is also true with some tap water and most well water. If you deside to go with tap water use a dechlorinator that also removes chloramine and ammonia, if you have city provided water. If you have a private well check the pH straight from the tap. Test the same water after it has sat out 48 Hours or has been aerated for a few hours. If the water tests acidic from the tap and then climbs to a base then you will have to aerate it like the spring water. I like the description of "Faceoff". Appropriate for opening day of the NHL. LTE'S GO DEVILS

Ok, I'll keep that in mind with the spring water. But just a question. The fish that wouldn't eat before still won't eat. He's simming around, he's unclamped his fins, and he's making even bigger bubble nests then before. I was just wondering if I should be concerned that he won't eat. He doesn't even act interested in the food. He hasn't eaten in four days now. Any ideas or am I just worrying over nothing?

What is the temperature of the tank? Has he regained any color? Do the white specs look like grains of salt? Any other physical or behavior changes ( bloated belly, sunken in belly, protruding or missing scales, does he rub against objects or suddenly dart acroos the tank, take food in and spit it out)? It may take a while for him to eat after the bad water conditions. I am assuming the old water was toxic from ammonia or nitrite or was too cold. More likely a combonation of these. Just keep the water quality stable for now. If he has any of the above symtoms post it. The only thing I would try is maybe a small bag of frozen brine shrimp or other frozen "meat" food. If he doesn't eat it before it sinks, remove the uneaten food.

The sick fish got better and had been doing fine and acting normal for over two and a half weeks. But he was dead when I went to feed them this morning :( . He didn't appear sick so I'm guessing he just died of old age, even tho I've only had him a couple of months. I checked nitrate and ammonia levels and they looked good. Thought they would since I did a 67% water change friday. I have a ten gallon tank with a divider. I still can't help but worry about my other betta tho. Even if he does look healthy and normal. Just a little bored since he no longer has someone to show off to.

Sorry to hear. Maybe another buddy or remove the divider and try some other community fish for mates.