An Oscar, Jack Dempsey, heck I could go on forever. Many South American Cichlids will destroy plants to their liking, if you're just wondering if you can get the fish in a planted aquarium go to a store that specializes in fish and ask them, they can lead you to very good species for a planted aquarium.
Aquarium water should never be hot; depending on the type of fish you keep, the temperature will vary.Goldfish for example are best in 75F, but a betta prefers 80F. Do plenty of research about the fish you are considering for your tank before going out & buying anything.
It is never wise to mix animals from entirely different groups. Turtles are Amphibians and will wreck the water purity for tropical fish. They should be kept in a Terrarium not an Aquarium. In addition; most turtles are carnivorous, and will eat whatever fish they are housed with.
Snow.
I am aware that Angelfish and any kind of Frogs should NEVER be in the same aquarium so I do not know the answer to your question.
Plecostomus are algae eaters they are not carnivores. They are also tropical fish so they should never be in an aquarium with coldwater fish like goldfish. If your Plecco is eating your goldfish you must be doing something very very wrong. Work it out. They can live with your goldfish but this may happen, This is because you are not feeding them enough most likely.
It differs from aquarium to aquarium but it is generally just about seven and can go to about eight. It should never be below seven because that is too acidic for fish. Different fish prefer different pH. Some fish will like it around seven, others around eight and some in the middle of the two.
The pH in tropical systems should never be that low. Tropical systems need a pH of around 7.8-8.4. Always a little high with higher salinity and temperatures as well.
Simple answer is they can but it's not wise nor smart to do it. There are so many rapid ways of maturing/recycling your filter and aquarium that there should never be any need to put fish in an unprepared aquarium.
As a basic rule amphibians (Frogs etc) should never be included in aquaria with fish. They require totally different conditions and should be in a vivarium not an aquarium.
NO ! They require completely different living conditions (humidity, temperature ranges etc) and should NEVER be housed together !
Mollies are tropical fish and should be kept above 70F. Goldfish are coldwater fish and should be kept below 70F. They should NEVER be kept together.
The one planted on the Moon by the Apollo astronauts.