Community Tank?

Question
I have a 10 gallon aquarium which I have recently added a female betta to and am going to put mystery snails in to help keep it clean. Once it has been properly cycled with a filter and air pump would it be best to add platies and tetras or to add rasboras and cherry barbs? I have a separate tank for fry and I would never buy a live bearer without having someone to take them such as a pet store so it won't get overstocked. Also how many of each should I put in? It's a 10 gallon and I don't want it to be over stocked. There will be plenty of plants and hiding spots for them so that's not a problem. Also any advice on keeping the tank in perfect condition would be great as I havn't kept more then a betta since I was a kid Thanks.

Answer
you are doing things fine so far in that you're not in a hurry. The worst and first mistake people make is getting impatient to add fish. The second most common error is feeding too much too often.
  A word on feeding: yes they sure look hungry. And they must need to eat or they'd leave the food alone, right? No!!! Fish are no different than other animals. They will eat as much as they can stomach because in nature the food may be gone tomorrow. If you forget to feed them a few days they won't die. If you think you are feeding the right amount then cut that in half.There are floating feeders where the fish take food out as they want. But those never work right.
Ok that wasn't your question. The Platties.I would hold off on getting the live bearers for a while. (swordtail, platties, mollies, etc). A new tank will have problems. No matter if you had the best plans and methods something will get messed up. Expect that but DO NOT PANIC when it does. The water doesn't get messed up overnight. It won't get better overnight. The live bearers are more sensitive to diseases. If you have a minor problem they will feel it first. For that reason you don't want to waste money. However, on the other side of the coin is that they will tell you when something is wrong earlier. When your tank cycles get whatever egg layers you like. In general they are tougher. I suggest for a first fish...Tiger Barbs. At least 3 because they behave better in groups. You will hear that they have a bad temper or attack other fish. That idea is populated by people who want only 1 or 2.  Get 4 make them happy.
How many fish can you have? The basic rule is  one inch of fish per gallon. The gives you 10 inches of total fish. The Tetra, Barbs, Platties are 1.5" so that doesnt leave you many fish. Maybe 8 to be safe. Maybe 14 if they are smaller.
   Advice? There are books and books about it. I can't tell you it all.
To start with your tank is too small. you will crowd in too many fish because you "just had to have those 3". Everyone ends up getting a bigger tank. Bigger is easier. A small tank is more work because less water builds up bad things faster. Keep the 10 as a breeding tank and go buy at least a 30. A good filter is manditory. There are 2 types. Overflow type which hang on the outside or canaster type which run the water through tubes. I prefer the canaster type because they clean better and it allows the tank to be viewed from both sides if theres no filter hanging on one side. If you have the hang-on the side type you will be using those slide in cartridges. HINT: there is not enough charcoal in those to last long nor clean well. That is so you have to buy more. Buy the biggest can of activated charcoal you can find. Cut a small slit in the blue/white fiber. Spoon in as much charcoal as will fit. It will clean better. Weekly dump out the charcoal and spoon in new. Rinse the cartridge & padding well then put back in the filter. Throw the cartridge out every 5 weeks. Charcoal is what keeps the water clean. Not air. Not circulation.
  In a canaster filter squeeze in as much charcoal as it can hold. These use foam and other "easy to slide right in" devices. I use loose charcoal and loose filter fiber (the white cottony stuff) in any filter I have. The cartridges are easy to be sure but I feel they don't clean well nor last long. "The easy way" is promoted because it makes $$$$$$. however you do it get more charcoal in the filter system.
HINT: it says to rinse the charcoal. It says that because people think the black water from carbon powder will kill the fish. It won't. If you do not rinse the charcoal before you use it, then the powder turns you water black. It will go away in an hour. It settles in the gravel which is where all the bad creepy things are. There, it helps kill a few of them. Which is what charcoal in the filter is supposed to do. THis does NOT mean dump in some charcoal as a precaution. LOL!
   Ammonia will be your worst enemy to control. You can buy charcoal that has white chips mixed in....brand is AMMO-CARB. The white chips remove the Ammonia. The white chips can be bought seperately.
HINT: the are no "slide-in" cartridges containing the white chips. Another reason to cut the slit and add some.
 PH is second most important. Over time it will go down from fish waste, food, etc settling in the gravel. Rarely will PH go up by itself. To raise the PH you can go buy one of those little bottles of "PH UP" stuff at the cost of $5.95 plus tax. Or...
HINT: go to your kitchen and get the BAKING SODA. Add 1/4 teaspoon per 10 gallons every 3 days until the PH gets up where you want it. Go read the label on the stuff at the store...ingredients>>>>>water, SODIUM BICARBONATE, blue dye. The store doesn't want you to know that.   $$$$$$
HINT: if you have hard water you can add 1 teaspoon of SEA SALT ( no not table salt). It will soften the water.
Speaking of salt....Swordtails, Platties, Mollies require a bit of salt in the water. They live where the river meets the sea. Other fish may not be able to handle the salt. For that reason be careful when you choose live bearers.
You already know to float the bag of fish in the tank 15 minutes right? Then open and add a cup of your water to the bag. Repeat the adding 3 times. The fish are now aclimated to your water. Get you net and pour the fish into the net over the kitchen sink or a bucket.  Quick put the critters in the tank. NEVER PUT THE STORES WATER IN YOUR TANK. NEVER!! There are nasties in the store water but they only have the fish a few days and get sold.
Go ahead add a Male Betta when the water gets cycled. A blue one. LOL!! I'd pick green but they don't come in green.
HINT: Painted tetras are just that....painted with special paints. The paint will come off in 2 weeks at home.
Add an air stone for circulation. Plus the bubbles just look cool. Live plants will help keep the water clean. Real plants need 10 hours of light/day.
Plants....Java Ferns are real strong. Dwarf Lily grow fast like 10" over night.
Perfect condition?  there is no such thing. Keep the water a constant 77 degrees. That temp should make most everything happy. Mollies like it 82. Tilipias like it 85.
Keeping the Ph at 6.5 should be safe for all.
Watch the Ammonia level. High Ammonia is a reason to get to the store and fix the error fast.
If you use well water...DON"T. Find a friend who has city treated water and steal theirs.
Eventually you will get Ick. Hopefully not but most do in the beginning. Ick is the most common parasite but there are others. The best stuff made to get rid of ALL parasites is  MARACIDE. Its not cheap but the best.
Go to a local "FISH STORE". I don't mean that national chain. I mean the guy in town who has a little store and sells FISH. Makes his living that way. You will get the best advice there. Yes his stuff costs more but that chain store (shhh petsmart)has no clue what they're doing. Wally World fish? OMG NO!!
You're doing fine. take it slow. Add 1 or 2 fish per week. see how they do. If 1 dies take tests or try to figure whats wrong. In the end there are sometimes when you will scratch you head. chalk it up to experience and go get another fish. Never move everything around the tank at once. Minor changes over time are better. The fish don't care where that stump is.
Breeding fish.....The fry need Live Brine Shrimp.  Those you'll need to hatch at home. Your fish guy can explain how.
Email me direct at....hancallaway@yahoo.com
You'll  get a bigger tank. Everyone does.