How do I set up a saltwater tank? First and foremost, you need an aquarium. The bigger, the better. Before finalizing on a tank size, remember that dish densities are much lower for saltwater than freshwater. That is, you can not put as many fish in a saltwater tank as you can in a freshwater tank. Putting more than 2 saltwater fish in a 10 gallon tank is asking for trouble. A general rule of thumb is 4” of small-to-medium fish per 10 gallons or 2” of larger/faster growing fish per 10 gallons. This is just a rough estimate of the number of fish. There is no exact number since finding the stocking density has to take into account the filtration, maintenance, feeding schedule, etc. Second, you need filtration, heating and lighting. You can never have enough filtration in either salt or fresh tanks, so buy the most efficient filter to suit your budget. You may also consider protein skimmers. Trough not necessary in fish-only aquariums, most saltwater hobbyist will tell you this is a must have for reef tanks. Protein skimmers are very effective at removing various organics, like protein, phosphates, and fatty acids from the surface of the water, which takes a huge load of the biological and mechanical filtration systems. As far as heating, you’ll need to refer to the species you’re keeping. Some saltwater fish are tropical. They live close to the water’s surface and prefer warmer water. Other fish may come from greater depths in the ocean and require a chiller added to the tank in order to keep the temperature lower for them. The lighting depends primarily on what kinds of fish and/or corals you plan to keep. Fish and organisms that live in the deeper water will often require lighting that leans towards the blue end of the spectrum. In most fish only aquariums, you may use a simple full spectrum fluorescent lighting. Third, you’ll need a substrate. In freshwater tanks, you have an assortment of colorful gravels to choose from. With saltwater, this in not the case. Gravel contains copper which is harmful to invertebrates and corals you may want to keep in your tank. Instead, you’ll need to use materials that are specifically for saltwater use. Marine sand, crushed coral, argonite, dolomite, etc. Saltwater is capable of dissolving metals, so avoid putting any metallic décor in the tank unless the item is specifically for saltwater use. Saltwater parameters: In order to make saltwater, you’ll need a saltwater mix and a hydrometer. In a large bucket, you’ll need to mix dechlorinated water with the saltwater mix until the hydrometer reads at 1.021-1.023. Marine pH is critical to the fish and invertebrates you keep. A pH of 8.0-8.4 can be tolerated by most, but fluctuations can be detrimental to the fish health. If you intend to keep live rock, corals, and other invertebrates, you’ll need to supplement the tank with calcium, iron, iodine, and other essential elements in order to keep them healthy. Prior to adding any fish to the aquarium, it will need to cycle. This is the same process that freshwater tanks must go through in order to keep healthy fish. However, when dealing with saltwater, patience in a virtue. Rather than waiting a few days and then dumping a tank’s worth of fish as most people do with freshwater tanks, saltwater tanks require a longer cycling period. A minimum week to a full month is suggested. The longer you wait and allow your water to age, the better your chances for keeping a thriving stock of fish.