romanda or orandas In pond

I adopted 4 of these goldfish. My pond is 300 gallons. Ihave them in a
30 galloon tank that Is ro small. I have 2 filters. Anyway. Can I put
these in my raccoon safe pond in march? The water temp is then 65. My
problem is that the temp in summer hits 84 with shade. Is this safe for
them? My comets do well. But Im told that these need 75 ect. Can they
cope with a slow temp change? And is there a good bacteria additive for
any problems? My comets did well for 4 yaers. These would be in the own
300 gallon pond. also what is a good preventive bacteria/ parasite
addite? Thank you