Otocinclus Catfish Breeding - My Observations of Week 1

tldr;
Parameters:
29g planted stocked with 7 adult otos, 12 rasbora, 2 adf, 2 bamboo shrimp, assassin snails (betta was separated)
78f heated treated tap water
no ferts or co2, inert substrate over flourite
ph ~6.3-6.5
low alkalinity
nitrite 0
nitrate 20-40ppm - plants keep it pretty stable
hardness of about 125mg/L (mostly from snail shells and crushed eggshell)
40 percent water change with cooler water triggered

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This is the first time my otocinclus catfish have attempted to spawn. I am not an expert on otocinclus and unfortunately was unsuccessful past a week of raising the fry on this attempt.

However - I would like to try to give as much information as possible and talk about my observations of the spawning and first week so maybe somebody else could replicate this and successfully breed more tank bred otos!

I have 7 adult otos, 3 are O. macrospilus species, the other 4 are O. Vestitus.
There is 3 females and 4 male, and as of the making of this video, all 3 females are gravid and males are ready and just waiting for the female to accept.
Before the spawning occurred, there were no major changes to the aquarium in at least the previous 2 months.

I believe a cool "rainfall" water change and drop in water level simulating a rainy season is the main factor in triggering the spawning behaviour, and I will try to replicate this in the future.

I made some Oto MERCH!
https://flying-shrimp-photography.cre...