This is an assorted pack of 7 large acorn caps from Burr Oak trees and Sawtooth Oak tree. Four of the large acorn caps have a fringe, and three do not have a fringe. These caps are about the size of a US quarter. Isopods and springtails enjoy acorn caps and they make excellent ground scatter in a terrarium. These will also release tannins in a blackwater aquarium. Product Details: Source Location: USA. Size: Approximately 1 to 1.25 inches in diameter. 100% Natural: Organically sourced and naturally dried, these caps are free from artificial chemicals, making them a safe and sustainable choice for various applications. Highly Versatile: Aquarium: When properly prepared, they can release a moderate amount of tannin, promote biofilm, and they provide unique hiding spots and contribute to a natural environment which stimulates natural behaviors for fish and shrimp. Bioactive Terrariums: Provides hiding spots and a food source for isopods, and springtails, enriches the substrate by releasing nutrients as they break down, and encourages natural and instinctive behaviors such as forging and exploring. No additional preparation of the botanicals is necessary for bioactive enclosures. Preparation for Aquarium/Paludarium Use: Boil: Boil the caps for at least 10 minutes to help them sink and leach initial tannins. Soak: Soak in clean water overnight or longer if needed, changing the water daily, until they are fully waterlogged and the desired amount of tannin has been leached. Ready to Use: Once they sink and you've achieved your desired water coloration, they are ready to be added to your setup. Please Note: As a natural product, each acorn cap is unique and will vary in size, shape, and coloration. These acorn caps are intended for decorative, craft, and aquarium/vivarium use only and are not for human consumption. SHIPS FREE WITH LIVE ANIMAL PURCHASES