Possible Courtship and Spawning Behavior in Tetraodon biocellatus – Observation from August 3, 2024Hi everyone,
I’d like to share a detailed observation of what appears to be active courtship or pre-spawning behavior in my group of Tetraodon biocellatus (figure-eight puffers). I’m very curious if others have witnessed something similar – happy to exchange insights!
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Tank Setup & Parameters• Tank size: brackish aquarium
• Stocking: 4 T. biocellatus
• “Bomble” (likely female)
• “Bubbles” (likely dominant male)
• “Stromble” (likely subordinate male)
• “Womble” (neutral, shows no mating interest)
• Water parameters after morning water change (9:00 AM):
• Salinity: 14 ppt
• pH: 8
• Temperature: 25 °C
• Simulated sunrise lighting started at 23:20
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Observation Timeline (starting 23:30, August 3)23:30 – 00:30
• Bomble repeatedly lays on the exact same spot in the sand, staying active, darker in color.
• Bubbles observes Bomble closely, defends the area aggressively, but does not lie on the spot.
• Stromble occasionally lays on or near the same spot, often parallel to Bomble.
• Bubbles begins to chase away Stromble and Womble, and later even Bomble herself.
• No visible eggs detected by 00:30.
00:40 – 01:01
• Bubbles shows three instances of light belly inflation toward Bomble – subtle and short.
• Bomble and Bubbles face each other occasionally, remain near the potential spawning site.
• Stromble presents sideways to Bomble, darkens visibly, and lies flat on the substrate.
• At 00:58, Bubbles begins rubbing against objects.
• 01:01: Stromble also performs a slight belly inflation toward Bomble.
• Bubbles remains on top of the rock structure, watching passively.
• Womble stays neutral and roams the opposite end of the tank.
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Interpretation• Bomble appears to be spawn-ready (focused site behavior, darker coloration, active)
• Bubbles acts as the dominant courting male, defending the site and displaying
• Stromble emerges as a possible subordinate male rival, actively displaying later
• Womble seems completely uninvolved
Despite strong courtship signs, no actual egg deposition occurred. Possible reasons:
• Timing mismatch or unresolved mate choice
• Slightly high salinity (14 ppt; optimal might be 10–12 ppt)
• Temperature could be a bit low (25 °C vs. 26–27 °C ideal)
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Has anyone observed similar behavior?• How often is this kind of structured courtship seen in captivity?
• Did your puffers eventually spawn after a few days of similar activity?
• What does the actual spawning moment look like in this species?
I’m continuing to document everything (including timestamps, role patterns, and physical cues) and can share updates if there’s interest.
Best regards,
Anny
still hoping the be the *special* one.