Different Types of Saltwater Aquariums Saltwater aquariums should generally contain fewer fish than fresh water tanks, because the species tend to grow bigger in size. Marine species may be bred in a captive environment, or caught in the wild. Captive bred species are easier to care for and usually hardier than caught species. In addition, you will need to purchase a filter for the tank. Filters can be complicated. Do a lot a research to find out what type of filter is suggested for the fish that you choose. There are filters that go beneath the substrate in the bottom of the tank, as well as filters that attach to the side of the aquarium. Unfortunately, it is not realistic to go the pet store and just start picking out fish. Take a trip to the pet store in order to gather information and window shop to determine the types of fish you wish to keep in your aquarium. Carefully research these fish to ensure that they are compatible for water temperatures and P. The low growing plants, or plants with multiple leave levels will suffer from a lack of light as the florescent rays will not provide enough light. Once you have figured out what type of lighting you will use, you must turn your attention to the hardness of the water. The majority of aquarium plants will thrive in water that has a hardness between 4-12 dH, and between the range of 6.5-7.2 for pH. This bacteria is essential to have and helps in breaking down waste products in the tank. Overall, the use of live plants aids keeping your aquarium clean and healthy while adding a perfect visual effect. Once the decision to use live plants is made, you must familiarize yourself with how to grow and care for these plants. The supplies you will need to set up your aquarium may seem lengthy, but it is actually a much shorter and cheaper list than that of a heated freshwater tank or a saltwater tank. Obviously the first thing you need is a tank. It's all about personal choice here as they come in many sizes and shapes. When you purchase the tank, a kit often comes with it and includes some of the other things you may need.