Hobby Catappa Leaves XL Aquarium Botanicals - 12 Pieces

Hobby Catappa Leaves XL Aquarium Botanicals - 12 Pieces is twelve extra-large Indian almond leaves, the single most widely used botanical in the hobby. They sink on their own after a day or two and then slowly release tannins. What tannins actually do is tint the water the colour of weak tea and nudge pH and hardness down a little - which is exactly the water that South American and South-East Asian soft-water fish and shrimp evolved in.

Key Features

• 12 XL Leaves, enough for up to 1,200 litres according to Hobby.
• They Sink By Themselves. Drop them in; they waterlog and go down within a day or two.
• Biofilm For Shrimp: as a leaf softens it grows the biofilm that shrimp and fry graze on. For a shrimp tank that is the main point.
• Releases Tannins: a gentle, gradual drop in pH, and the tea-coloured water that gives blackwater tanks their name.
• Natural, Single Ingredient: no dosing cap, no chemistry set.

What Hobby Claim, And What To Expect

• Hobby describe these as helping prevent ailments and reduce stress. Tannins do have mild antibacterial and antifungal activity, and blackwater conditions genuinely suit the right species. But treat this as husbandry, not medicine - a botanical is not a treatment for a sick fish, and a fish that needs medicating needs a vet or a proper medication.
• The water will go brown. That is the product working, not a fault. If you want the benefit without the colour, run carbon - though carbon strips the tannins too, so you cannot really have both.
• The effect depends on your water. In hard, well-buffered tap water - which is most UAE supply - tannins shift pH far less than they would in soft water. You may get the colour and very little chemistry.

Using Them

• Start with a fraction of the dose. Add two or three leaves, wait a week, test, then add more. Hobby's up-to-1,200-litre figure is a maximum, not a recipe.
• Change water chemistry slowly. Fish cope far better with steady-but-imperfect water than with numbers that swing about. Move pH and hardness gradually and test as you go rather than dosing to a target.
• Leave them to break down rather than pulling them out. The slow decay is what feeds the biofilm. Remove them only once they are falling apart.
• They use a little oxygen as they decompose, so do not bury a tank in them at once, especially a warm tank in summer.

Good To Know

• This listing is the pack of 12 XL leaves.
• Rinse them first and, if you like, pour boiling water over them - it makes them sink faster and knocks back anything on the surface.
• Keep the pack dry. Damp botanicals go mouldy in a UAE cupboard faster than you would expect.
• Not a substitute for water changes. Nothing is.