Treating Tetras with eSHa 2000: Mouth Fungus & Cotton Wool Disease
Tetras are beautiful, but they can be incredibly fragile. If you see white fluff around their mouths (often called "Mouth Fungus," though it's actually a bacterium named Flavobacterium columnare), or if a single fish in your school starts looking "fuzzy," you need to treat the whole tank immediately. In a school of Tetras, an infection can spread from fish-to-fish in hours.
eSHa 2000 is the specific medication I recommend for Tetras. It’s effective against Columnaris and other "fuzzy skin" diseases, and most importantly, it's remarkably gentle on small, high-metabolism fish. It won't crash your school if dosed correctly.
The Mouth Fungus (Columnaris) Scare
If you see white patches around the mouth or a "saddle-back" mark on the top of your Tetra, you are likely looking at Columnaris. This isn't a fungus; it's a fast-moving bacterial infection. If left untreated for 48 hours, it will likely be fatal. eSHa 2000 acts as a broad-spectrum antibiotic and antifungal to stop this in its tracks.
Safe for Small Fish
Tetras are highly sensitive to "concentrated" chemical spikes. When using eSHa 2000, never pour the drops directly on the fish. Mix your dose in a small cup of tank water and pour it into the filter output over a period of 5 minutes to let the fish adjust.
Step-by-Step Tetra School Dosing
Since Tetras are small, precision is everything. A single extra drop in a small tank is a much larger percentage of the total water volume than in a big tank.
Get the exact drop count
Don't gamble with your school's health. Use our eSHa 2000 calculator to find the perfect dose for your net water volume.
Calculate My Tetra Dose →Special Tetra Considerations
Neon Tetra Disease (NTD) vs. Fungus
Neon Tetra Disease (Pleistophora hyphessobryconis) is often incurable, but it usually starts by looking like a loss of color or a "lumpy" body. True Fungus looks like cotton wool. If you aren't sure, treat with eSHa 2000. It covers the secondary infections that often kill fish infected with NTD, giving them a better chance to recover their strength.
Planted Tanks
Tetras live in planted tanks. eSHa 2000 is plant safe. You don't need to worry about your beautiful Rotalas or Anubias melting away while you treat your fish. It's the "set it and forget it" solution for a high-value aquascape.
Oxygenating the School
Tetras have high oxygen demands. All medications lower oxygen levels slightly. Add an air stone or increase the surface agitation from your filter during the 3-day treatment. Clear, moving water is a Tetra's best friend when they are fighting an infection.
Conclusion
Don't wait for your whole school to look sick. The moment you see a "fuzzy" fish, start the 3-day eSHa 2000 protocol. It's effective, gentle, and the best way to ensure your colorful school stays intact. Follow the dosage, keep the water moving, and keep the lights low to reduce stress during recovery.
Written by Richard James
Tetra enthusiast and aquascaping expert. I help you navigate fish health without sacrificing the beauty of your planted aquarium.
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