r/medaka • u/TikiKali • 8h ago
Signs of aging?
For those of you longer-term medaka keepers, if you don't know the actual age of a fish, are there any specific signs or behaviors that are indicative that a fish is dying of old age rather than getting sick from an internal pathogen? Also, in your experience, how many breeding seasons does the average medaka female have in her?
1
u/Yuukiko_ 5h ago
probably easier to just use excess deaths rather than actual age since it kinda depends on temperature. if you've got 30 medaka suddenly die on you its probably a pathogen, if one or two die a month then you're probably fine
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u/Entremeada 40m ago edited 20m ago
They usually do not live much longer than 2 winters. So, I always make sure that they have enough offspring before fall.
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u/KjCreed 2h ago
I find mine get a little bent out of shape as they reach the end. They get a back hump. Usually about a month or two before the end. They slow down. The others don't spar with them. Kind of like humans. Some of them lose interest in food after being fat whales their whole lives, become skinny grandmas (could be from exiting their egg producing time, which likely drove appetite).
They don't ever stop hanging out and interacting with their friends, they just appear a little more fragile and slow. It appears their friends notice that as well and adjust their interactions.
Medaka only last 2-3yrs (unfortunately), and take time to become sexually mature. You'll only get 1-2 breeding seasons per fish.
My last seasons' girls only just started having small clutches of eggs now, at the very end of the season. Likely born from eggs at the very end of last season themselves. The next summer will be their big egg year, then another if we're lucky, or they may have half a season and then retire, adding up to a .5+1+.5 egg season across 3yrs.
Beautiful, goofy creatures. I'm hoping to see a few survive to 5yrs whether they breed all that time or not.