new fish bought

Question
Hi Alex, I have a 30 gallon aquarium and just put in it 1 tin foil barb, 2 silver dollars and 1 bala shark.  Do you think this is a good combination?  They seem okay now but they are all quite small.  I know the tin foil and bala shark can get pretty big.  In your opinion is this the most I should add to my aquarium? I wanted to get two more bala sharks or one bala and another tin foil since I hear they're schooling fish.  Your opinion really does matter if you say "NO MORE!"  I will take the advice.  Also, how often should I feed them and how often should I do water changes with these types of fish.  I had an African chiclid before these for a little over 4 years and it died of dropsy recently.  I don't want to go through that again.  Again, they are pretty small right now.  The tin foil is maybe a little under 2", the bala is perhaps the biggest at maybe a little over 2", the silver dollars are just a little over 1".   Thanks in advance!

Answer
Hey Sandra,

Well you got some very nice fish there, but i think you might have picked the wrong fish for you type of aquarium. This is what i hate about pet stores they dont make you aware of how big these fish actually get. That tinfoil can grow to a little over a foot. They are schooling fish but i cant see putting 6 of those in your tank. You also have a bala shark (i only keep one in my tank) which grow to over a foot at full growth aswell.  Your silver dollars will grow to be about 6 inches at full growth. I think you'v picked some fairly good community fish but i think your tank size is going to be too small in a while. I would suggest a tank of at least 55g or more. I would not suggest adding anymore fish until you can get a bigger aquarium. In myopinion when these fish grow up your tanks going to look funny with only 4 huge fish in it lol. But on the good side your goin to have all nice community fish. You should not overfeed fish, feed them enough once a day where they eat as much as they want but stop once they are done. Water changes should be done every week, i do a 50% water change on mine. I suggest you have a canister filter such as a eheim or a fluval it will help alot.

I suggest you read up on your fish and see what other requirements each need. :)

Good luck