Seasonal fluctuations for juvies too?

[ashik]

I was thinking about wet/dry seasons for trying to breed my L260s when the thought dawned on me that even juveniles might benefit from seasonal changes too.
I was thinking that perhaps fry can have better growth rates if they go through more natural seasonal changes too. Ie, having a restricted or smaller feeding for a while with lower slower water, then simulating a wet season with greater feedings. It seems more natural to me, and possibly might help growth rates too, as they'd instinctively get big in a hurry during the wet season in nature, why not in a tank? I don't have the space or the fry to test this with, but I think it would be neat to see if it makes a difference.

What do others think about this?

[Bas Pels]

It might work out properly, in fact I think fishes should be kept much more thinking of the normal flutuations in their habitat. However, in this case the first think I'm thinking of is - how large will the average fry be when the bad, dry season hits

but also, is the dry season really a bad one? In the dry season many fish die. However, I can imagine a flesh eating Hypancistrus would benefit from this

I only intend to say - natural fluctuations might be a good idea, but before one starts to fluctuate a tank, it would be better to know what th fluctuations will mean

[apistomaster]

I personally would not subject juvenile Loricaridae to simulated seasonal fluctuations because I can not conceive of any reasons why they would benefit from them. It is a useful technique to use for inducing adult fish in breeding condition to spawn but the real effect of the dry season in the wild is the loss of many young of the year and it is a period where predation and losses due to entrapment in isolated waters subject to drying out occurs. Those that survive are the lucky ones who happen to find themselves in a more stable environment with all the qualities needed for survival. To my way of thinking, I would think in an aquarium the juveniles would best be treated to good conditions at all times. Once they appear to be old and mature enough to spawn, then subject them to simulated rain fall induced freshets.

It is possible to take simulating nature in the aquarium to extremes. In nature, each year, much of the the fish population is lost due to predation, overcrowding and decreased water quality. How does an exacting simulation of nature serve the best interest of the fish keeper and his fish?

[TwoTankAmin]

I agree with Larry. I am not aware of any fry that do not grow faster when given ample quality food and very clean water.

Most animals, fish included, have evolved to reproduce in a way that insures the survival of the species but not necessarily the survival of the maximum potential offspring. When we spawn fish, we tend to try for the highest survival rates and the healthiest fish. And we cull those that are "inferior" to keep the gene pool strong as well. In nature the weak rarely survive anyway.

I doubt that subjecting juveniles to seasonal changes would do them any harm, but I can not see it providing an additional benefit either. I have always left about 1/3 of my zebra fry in the breeder tank which has gotten mini dry seasons a few times over the past couple of years.