If you are hoping to replicate a natural look for your aquarium with minimum fuss then the replica baserocks from Unipac are what you need. Replicating nature with attractive rocks that will give your aquatic residents plenty of nooks and crannies to make it feel like home. Please rinse gently with cold water before use to remove any dust or particles. No need for chemical cleaning or use of abrasive sponges to clean. Aquarium enviroment should always be stabilised before introducing fish. 34cmx20xm