How to Care for a Spotted Puffer Fish

Buy a tank suitable for your requirements. A 20-gallon tank is ideal for one adult puffer, but if you intend to plant the aquarium or house other fish with your puffer, a 50-gallon tank is more appropriate.

Wash the gravel or sand and spread evenly over the base of the tank. Add rocks, decor and plants to provide plenty of hiding places. Attach the heater to the back wall, inside the tank, diagonally for optimal heat dispersal. Place the filter centrally on the back wall or follow the instructions on an external canister filter.

Mix tap water and marine salt or Instant Ocean in a 10-gallon bucket or large container. Follow the instructions on the packet to achieve brackish water of 1.010 specific gravity and check the salinity levels with a hydrometer. Add water conditioner to the brackish water to remove chlorine, chloramine and other chemicals that are found in tap water to make the water safe for your puffer fish. Add a few drops of beneficial bacteria solution to stabilize and cycle the aquarium to prevent a build-up of ammonia, nitrate and nitrite.

Pour the water into the aquarium and switch on the filter and heater. Set the heater to about 78 degrees F and monitor the ambient water temperature with a digital probe thermometer, aiming for a stable reading of between 74 and 82 degrees. Set the aquarium lights to be on for eight to 10 hours a day.

Check the pH level of the water with a test strip. Puffers prefer slightly alkaline conditions but they are fairly adaptable with pH so anywhere in the region of 7.5 to 8.5 is good. Mix a handful of crushed coral or aragonite into the substrate to achieve the required pH if necessary.

Carry out a water test at least once a week for the first month to make sure there is no ammonia, nitrate or nitrite present in your aquarium. If any of these toxins are allowed to develop unchecked, they will kill your puffer. Change 25 percent of the water once a week and add beneficial bacteria solution at the recommended dosage at least once a week as a precaution.

Offer your puffer fish a varied fresh food diet, not commercial flake or pellets. Shrimp, krill, bloodworm and cockles are all highly nutritious and live food will allow your puffer to engage in his natural hunting behavior. Alternatively use frozen food but always defrost it first.

Provide shellfish such as cockles or water snails to keep your puffer's beak in good condition. If a puffer doesn't eat shellfish and grind down its beak, the beak over-grows and the fish is unable to eat.

Feed your fish once or twice a day and remove any uneaten food with a net after about 10 minutes. Puffers are voracious, messy eaters and leftover food quickly goes bad, creating unhealthy water conditions.