Ready to step up to a saltwater aquarium? Here's what you'll need to know.

Water: For environments with no corals, use a high-quality salt mix that accurately replicates ocean water. For a Reef environment with live rock and corals, use a salt mix that contains extra calcium and trace elements and vitamins to support sensitive corals. Follow the ratio of salt to water listed on the packaging, and always do the mixing in a separate container. Do not mix or add the salt directly to your aquarium.

Tips: It helps to use a circulation pump in the container for fast dissolving of the salt. Make sure the temperature is the same or close to your aquarium temperature before adding. For a Fish-Only environment, perform a 25% water change once a month. For a Reef environment well-stocked with hard and soft corals, you may consider a 25% water change every two weeks.

Water Testing: A good quality testing kit is recommended. Regular tests will help you adjust your water parameters to avoid any problems.

Water Parameters
Water Temperature
  • Optimum 78°F; but livestock can accept a range of 76°F to 82°F
  • Fish-Only (Instant Ocean Sea Salt) 1.021;
    Reef (Reef Crystals) 1.024 to 1.026
Ammonia and Nitrite
  • 0
  • 0 to 10ppm
  • 9 to 12
  • Optimum 8.3; acceptable range 8.1 to 8.3
  • 410mg/L to 450mg/L
  • 0
  • 0
  • 1240mg/L to 1400mg/L

Filtration: For smaller marine environments (and budgets), a good option is either a hang-on tank filter, such as the Emperor 400 with a media basket to add carbon and phosphate remover, or a canister filter with trays to add several types of media.

Protein Skimmer: Whether a hang-on or in sump unit, a skimmer will remove excess proteins (liquid waste) from the water before it breaks down and becomes ammonia and is a good addition to regular filtration.

Sump Unit: Recommended for larger aquariums, a sump is basically a large acrylic box located beneath the aquarium that holds a skimmer, heater, return pumps, sponge filters, and bio media.

Water Circulation: Water movement is a natural part of the ocean––it carries food to the inhabitants and moves waste to the filter. So in addition to the primary filter system, a power head (two or more for larger tanks on opposite sides and heights) is used to create a circular water current to prevent any “dead spots” and simulate the natural currents of the ocean.

Lighting: Proper lighting is essential and can vary depending on the type of environment. A Fish-Only environment is the simplest, as any lighting made for marine and general viewing is fine. For keeping corals, a minimum of 5 watts per gallon is required.

Example: A 50-gallon Reef aquarium would need at least 250 watts of light. There are many types of lighting; however, LED is fast becoming the lighting of choice.

Substrate: This is the base of your environment. You can have a bare-glass bottom, but most hobbyists prefer a sand bed because many fish and animals use the sand for sifting, nesting and living. A live, fine sand is recommended, generally ½” to 2 inches in depth. Aragonite can also be used. Do not use pebbles.

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