Saltwater Aquarium & Reef Supplies

Saltwater tanks take more equipment and consistency than freshwater, but they are very doable for a careful beginner. The main extra steps are mixing salt to the right salinity, running a protein skimmer, and keeping parameters stable. Start with a fish-only or simple setup before adding corals and the learning curve is manageable.

A saltwater tank usually cycles in 2 to 6 weeks, often faster when you start with quality live rock that seeds beneficial bacteria. As with freshwater, you are waiting for bacteria to convert ammonia to nitrite and then nitrate. Test until ammonia and nitrite read zero before adding livestock.

At minimum: a tank, a filter or sump, a heater, a powerhead for water flow, a protein skimmer, and a reef-quality light if you plan to keep corals. You will also need marine salt mix, a refractometer or hydrometer to measure salinity, live rock, and a test kit. Browse the saltwater gear we recommend below.

A protein skimmer removes dissolved organic waste from the water before it breaks down into nitrate, using fine bubbles to pull proteins out of the tank. For reef tanks and heavily stocked saltwater systems it is one of the most valuable pieces of equipment. Small or lightly stocked fish-only tanks can sometimes manage with frequent water changes instead.

Live rock is porous reef rock colonized by beneficial bacteria and small marine life. It is the biological backbone of most saltwater tanks, providing natural filtration and a home for corals and fish. A common guideline is about 1 to 1.5 pounds per gallon, arranged to allow open water flow.

Most marine fish and reef tanks do best at a specific gravity of about 1.024 to 1.026, or roughly 35 ppt. Mix marine salt with RO/DI water, let it fully dissolve and reach temperature, then measure with a refractometer before adding it. Keep salinity stable — sudden swings stress fish and corals.

A fish-only tank keeps marine fish (often with live rock) and does not require intense lighting or pristine parameters. A reef tank also keeps corals and invertebrates, which need strong reef lighting, stable water chemistry, and good flow. Reef tanks are more demanding but more rewarding — many hobbyists start fish-only and upgrade later.

A change of about 10 to 20 percent every one to two weeks suits most saltwater aquariums. Regular changes export nitrate and replenish the trace elements and minerals that corals consume. Always match the new saltwater to the tank in both temperature and salinity.

Hardy, forgiving choices include ocellaris clownfish, damselfish, royal grammas, and firefish. They adapt well and tolerate the small parameter swings a new tank can have. Add fish slowly so your biological filtration can keep pace with the bioload.

Yes — most corals feed through symbiotic algae and need reef-specific LED or T5 lighting at the right intensity and spectrum. Soft corals and LPS are more forgiving, while SPS corals demand stronger, more stable lighting. A standard fish-only tank does not need reef lights.