I need some reassurance, please.

If you plan on stocking further, maybe try another filter such as a Rena Filstar, for you the XP2 series would be a great addition to a 55. They are really easy to set up.
 
sumthin fishy said:
You should be ok with community tetras, they are hardy, but you could always add some things to the tank to soften the water. I would wait though, untill you have a basic idea of how to maintain your tank.
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I would be careful trying to soften the water, its probably better to maintain the natural pH/hardness of your water and get fish that normally hail from these water conditions in the wild.
For a 55 I would have suggested Lake Malawi Cichlids and your pH would be perfect for them. But there are plenty of fish that will do great in higher pH.
 
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