Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to feed tropical fish [title] Find out how your fish eat. [step] Different kinds of fish like their food at different levels of the tank. Their mouths are designed to approach food in a certain way, so you'll need to know their preferred way of feeding.

Ending1: For instance, a typical aquarium would feed saltwater fish such as trout and haddock. [title] Look for healthy, live-moving spaces. Ending2: Look at your fish's mouth to determine where it likes to eat its food. [substeps] Surface feeders have up-turned mouths for reaching up to the surface of the water. Ending3: But your fish needs to also follow a different feeding method than other fish because, unlike some other fish, they don't eat fruit and vegetables. This means this method fits into the survival guide for your fish, as it keeps your tank functional. Ending4: [substeps] Other fish like salmon are great for tropical fish. Blue fish that are small enough to consume smaller amounts of water from the tank, like the crabs can eat oysters in the water as well.

Answer format: ending1/ending2/ending3/ending4