Fritz Casuarina Cones

Fritz Casuarina Cones are natural seed cones that slowly release tannins and humic acids into the aquarium — the same compounds that turn natural blackwater habitats a warm tea color. They mildly lower pH, soften the water, and add gentle antifungal/antibacterial properties that bettas, shrimp, and softwater community fish thrive in. A staple botanical for biotope, blackwater, and shrimp tanks. Pair with live freshwater plants and explore our full water care & maintenance lineup.

Why Casuarina Cones

• Naturally adds tannins & humic acid — softens water and creates that classic blackwater look
• Mild antifungal & antibacterial — supports recovery and reduces stress on sensitive fish
• Great for freshwater shrimp — supplemental grazing surface as the cone breaks down
• Ideal for betta and biotope systems — replicates wild South American & SE Asian habitats
• 100% natural seed cones — no additives, dyes, or preservatives

How to Use

Rinse cones briefly under fresh water before use. Drop straight into the tank — they'll sink within a day or two as they saturate. Tannin release peaks in the first 1–2 weeks and tapers gradually over the following 6–8 weeks. Replace cones as they break down. For stronger blackwater effect, use more cones; for a subtle tint, use fewer. Safe to combine with cholla wood, almond leaves, and other botanicals.

Specifications

Recommended Pairings

• Galapagos Cholla Wood Branches — adds more tannins and shrimp grazing surface
• ZooMed Betta Mopani Wood — natural African driftwood for nano & betta tanks
• Aquavitro Shrimp Tall Hut — molting & breeding shelter for freshwater shrimp
• KatsAquatics Shrimpsicles — veggie-protein sticks for freshwater shrimp
• Browse all freshwater plants

FAQ

Will these stain my tank water?
Yes — that's the point. The release of tannins gives the water a warm tea/amber tint that fish like bettas and tetras love. If you prefer clear water, use fewer cones and run activated carbon to remove the color while keeping some of the benefits.

How many should I use?
A common starting point is 1–2 cones per 5–10 gallons. Adjust based on the tint and pH effect you want.

Are they safe with shrimp and fry?
Yes — shrimp will graze on biofilm that forms on softening cones, and fry benefit from the antifungal/antibacterial effects of the tannins.

Do I need to boil or soak them first?
A quick rinse is usually enough. Boiling briefly will speed up sinking and release tannins faster — useful if you want immediate blackwater color.