Fish: [tropical fish club] Can one beta live with other types of fish?

First, I am new to fairly new to the group so i thought I would ask a question and tell you a little about my tank and fish.

Can a a single beta live with other types of fish?

I have my new (to me, actually used) 55 gallon tank setup (used to be a 35) and I wanted to have a little more variety/color.

At the moment, I have 2 fancytail ryukin goldfish, 1 lionhead goldfish (triangular tail and no dorsil fin), 2 small golden loaches (very entertaining fish), 3 black mollies, 3 starburst mollies, and a little frog.

With the goldfish (orange and silver/white) and the starburst mollies (orange and black), I have a little color swimming around. The 1 loach is only 1.5 inches long and its color is pinkish. The other loach is 2.5 inches long and it is pinkish also. The 3 black mollies are black. ;-) and the 3 starburst mollies are orange with black tails.

My grandkids gave us the ryukin and the frog and that is how all this started. Them my grandkids (won) 2 goldfish at the fair but they were the kind that get 14-18 inches long so I gave them to a friend that has a goldfish pond. I purchased another ryukin and the lionhead to replace the two I gave away without them knowing. These two fish are only supposed to get around 6 inches long. That is much better for an indoor tank.

My wife wanted the mollies but I was able to talk her into getting two different types so we would have more variety.

I wanted the loaches. I had purchased one this summer but it had jumped out of the tank and when we found it, it was almost dead. We put it back in the tank. It was breathing and swimming a bit but it did not last the night. That fish was so fun to watch that I had to get a replacement. It took over 6 weeks to find one so I bought 2 when I had them brought back from Indianapolis Indiana.

I also have one lily bulb and 3 other plant bulbs (I forgot what kind but they look like long grass).

One thing I noticed since I setup the new tank is that my heater can not keep up.

Does anyone have a tank heater that they do not need anymore? Any size would help.

My tank is 70-72 based on the int tank thermometer.

I am open to any suggestions and thank you in advance for the help.

Paul