Poseidon Filter Rocks

Aquarium Rocks

Ammonia is the #1 killer of backyard and aquarium fish. Keep ammonia in check with natural Zeolite, Poseidon Filter Rocks.

Why Choose Poseidon Filter Rocks

  • Poseidon Pond Rocks enhance the ability of a ponds biological filtering capacity using 100% natural Zeolite to remove ammonia and other harmful toxic substances that build up from fish and algae.
  • Strengthen the biological environment and help keep your fish healthy.

How it Works

  • At the start of each season, in either mature or new ponds, there is a lack of nitrifying bacteria which controls ammonia and nitrite levels.
  • Fish can die of ammonia poisoning during the development of the biological filter during the first few weeks.
  • Poseidon Pond Rocks attract and hold ammonia, making an ideal surface for the growth of nitrifying bacteria. The healthy bacteria grow faster to produce a larger and more active filtering system to control ammonia levels in backyard ponds.


  • Pond Rocks are an excellent biological filter media, however will not replace particulate filtration methods.
  • Place in the same area as current biological media, leaving ample space for current conditions, minimal impact beyond reduced ammonia levels on aqua-culture is the desired effect.

Application Rates

  • 1lb of Pond Rocks for every 30 gallons of water or 10lbs of Pond Rocks for every 300 gallons of water.
  • Pond Rocks are roughly 2”–3” in diameter.
  • Pond Rocks are available in 5lb bags.