Influence of temperature and daylength on spawning

[Virginia ranchu]

Hey all,

I'd like to get your input on how best to stimulate spawning indoors. As a starting point, I'd like to share a few observations. Before constructing my current fishroom, I used to keep aquariums in rooms with Eastern and Southern exposure to natural sunlight. In one room, the morning sun would be very bright, and my fish spawned quite regularly. After moving to a new fishroom with no windows, and all fluorescent lighting, the incidence of spawning dropped significantly. Since my lights were not on timers, and because I turned lights on and off at irregular intervals, I wondered whether this was interfering with the fishes' reproductive cycle. I found a research paper on this topic which indicates that photoperiod is very important. I have since put all lights on timers, and spawning has resumed. If you are interested, read this paper.

http://rms1.agsearch.agropedia.affrc.go.jp/contents/JASI/pdf/society/33-1443.pdf

Cheers,

Rob

[Ajno]

Thanks for the article. I've noticed the fish love to spawn in my bedroom (the sun shines through the window) and hardly ever spawn in my living room. So this answers my question as well.

[goldfishforlife]

I was told when I was young to give as much natural light as possible. Preferably near a southern facing window. Also to open window(if possible) in spring to let temp fluctuate (day/night) with lengthening of days.. I have no idea if any of that is true or not. But I can understand the theory.

[HNLim]

Both light and temperature play a very important part. In out part of the world, our temperature stays almost constant throughout the years. More often than not, goldfish spawn almost always after a day of rain.