Epsom salts & SBD advice

[fantasybookworm]

I'm almost certain my betta boy has Swim Bladder Disease, and I'm also pretty sure it's because I was feeding him freeze-dried bloodworms. I just had a question on where I could buy epsom salts and if anyone has any other advice for what I could do for him. I have the information on what I've been doing and such below here, with the info form. Thanks for any help!

Housing
What size is your tank? 10 gal
What temperature is your tank? 76-80 degrees F
Does your tank have a filter? No
Does your tank have an air stone or other type of aeration? No
Is your tank heated? Yes
What tank mates does your betta fish live with? N/A

Food
What type of food do you feed your betta fish? Wardley Betta Food pellets & Tetra freeze-dried bloodworms (throwing these out though)
How often do you feed your betta fish? Usually once a day, in the evening.

Maintenance
How often do you perform a water change? Usually every 2-3 weeks.
What percentage of the water do you change when you perform a water change? 25-33%
What type of additives do you add to the water when you perform a water change? I use Tetra BettaSafe water conditioner.

Water Parameters:
Have you tested your water? If so, what are the following parameters? I haven't tested it.

Ammonia:
Nitrite:
Nitrate:
pH:
Hardness:
Alkalinity:

Symptoms and Treatment
How has your betta fish's appearance changed? After reading about SBD, I noticed he was looking a little round/bloated around his stomach, just behind his front fins, but that's gone down since I noticed on Wednesday.
How has your betta fish's behavior changed? He spends most of his time lying on the bottom of the tank and struggles to swim to the top of the water. He was still interested in food on Wednesday, but I haven't offered since after looking it up and starting to think it's SBD.
When did you start noticing the symptoms? Wednesday evening.
Have you started treating your fish? If so, how? Yes, I've moved him into a "hospital" tank (2.5 gal as opposed to his usual 10 gal) and kept the water level to just less than half full to make it easier for him to get to the top. I haven't fed him either pellets or freeze-dried worms since Wednesday, when he ate normally. I tried giving him some peas today (before reading that that's a no-no), but he wasn't interested anyway. Not sure whether that's him being smarter than me or if I should be worried that he's not interested in food. He seems to be less active today as well.
Does your fish have any history of being ill? No.
How old is your fish (approximately)? I've had him for just over a year and a half, I think, but I don't know how old he was when I bought him.

[aqua001]

U can get epsom salt at walmart. Be sure to dissolve it first. Also, you should probably change the water more often. I change the water once a week, 40 percent of it.