The Skeptical Aquarist

There's no real savings in a cheap heater that's not completely submersible. There are many better ways to save money when you're setting up an aquarium than by buying a "bargain" heater.

Capillaria are parasitic nematodes, smaller than Camallanus and proportionately very thin ("capillaria" mean "hair-like"). There are numerous species, most of which were originally from South America, where they co-evolved with certain specific hosts.

Crustacea are a huge division of the arthropods. Crustaceans fill most of the roles in water that insects fill on dry land.

This variable fern is the major floating plant for most indoor aquaria. In the aquarium it's so fast-growing and undemanding that it gains a place on even a rank beginner's list.

This is an African fern that runs along a rhizome the way Java Fern does, and similarly it doesn't want its rhizome buried.