How to Get Rid of Hydra in Your Tank

Hydra are freshwater relatives of coral and jellyfish. They attach to plants or other surfaces in the tank and extend their tentacles, waiting for small food items like baby fish or baby brine shrimp to wander into their grasp. These food items are stung by the tentacles and reeled in to the hydra's "mouth," which is at the top of its stalk-like body. While you can maintain a tank of hydra, they normally are seen as a pest animal. There are several natural methods you can employ to get rid of the hydra in your tank without having to resort to harsh chemicals.

Things You'll Need

  • Gouramis
  • Aquarium-grade salt
  • Aquarium net
  • Pail
  • Aquariums
  • Siphon with vacuum head
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Instructions

    • 1

      Add gouramis to your tank. These fish should consider the hydra as a food item. You can add blue gouramis , dwarf gourmais or sparkling gouramis. These are popular species; you can find them at any local fish store. Properly acclimate the fish to your aquarium's water chemistry by placing them and the bag water in which they came in a pail. Add a cupful of tank water to the pail every 15 minutes for two hours. Collect one fish at a time with an aquarium net and place the fish in your tank.

    • 2

      Remove your fish and aquatic plants from your aquarium and add 1 tsp. per gallon of aquarium-grade salt to the hydra-infested tank once a day for seven days. Freshwater parasites and animals like the hydra cannot tolerate the salt. It will stress and kill them. Perform a large -- about 90 percent -- water change before returning the fish and plants to the tank.

    • 3

      Raise the tank temperature to the high 90s or about 100 degrees. Your fish and aquatic plants will have to be moved to a different tank before doing this or else you risk killing them. Keep the temperature high for a few hours and then turn off your tank's heater. Remove all of the water from your tank, vacuum the substrate and wipe the tank's sides down with a paper towel. Add fresh dechlorinated water to the aquarium and turn your heater back to its original temperature. Wait until the temperature stabilizes before returning any fish or plants back to the tank.