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Pour the water into an empty, clean aquarium or fish tank. Measure out the right amount based on the number of Triops you currently have or expect to have after hatching. Use natural spring water, which has calcium to help the animals grow.  You can also use tap water, as long as it’s been treated to remove all chlorine, which is toxic to Triops. Do not use mineral or distilled water. The mineral level in mineral water is too high, whereas distilled water doesn’t have enough calcium for the Triops. Because Triops need warm water to hatch and thrive, set a lamp over the top of the tank to maintain a mild water temperature. Position either a fluorescent or incandescent light about 12 inches (30 cm) above the water.  Put an aquarium thermometer in the tank to monitor the water temperature. If the tank is sitting somewhere in the sun or in a warm room, you may not need the light to heat the water. Line the tank with soil, gravel, or sand so the Triops can dig around. Fill the bottom with about 1 to 2 inches (2.5 to 5.1 cm) of your chosen substrate to protect any larvae and prevent the Triops from mistaking the eggs for a snack.  You can buy the substrate at a pet store or from an online retailer. Wash the substrate with plain tap water before putting it in the tank to remove any potential chemicals or dirt. While Triops don’t require any plants or extra items, like large stones or fake castles, in their tank, you can put some in if you’d like it to look more appealing. Only use plants or decorations that are safe for aquarium use, however, so you don’t accidentally poison the Triops. Never put things you find in nature, like a rock or a log, in the tank as they can contain harmful bacteria. To keep the water fresh, replace about 1/4 of it on a weekly basis. Scoop it out with a cup or bucket, then pour clean, natural spring water in. Be careful not to scoop up the Triops with it! Do not use soap when cleaning your tank. It’s poisonous to Triops.

Summary:
Fill a tank with .5 to 1 gallon (1.9 to 3.8 L) of natural spring water per Triops. Place a heat lamp above the tank to keep the water between 72 and 84 °F (22 and 29 °C). Add substrate to the tank if you'd like to recreate their natural habitat. Choose plants carefully if you want to add decoration. Change out about 25% of the water in the tank once a week.