The Baby Q

[GaryD]

Hi Paul,

I did not say sub optimal, I said sub lethal, there is a big difference. Sub optimal is outside the species optimal growth range, sub lethal is where the fish are stressed and have an increased risk of disease and death. The range you are keeping these fish in is sub lethal, hence the death.

I didn't say you did say sub-optimal......and I understand the difference.

Just because you can keep fish "alive" in sub lethal environments, it does not make it morally correct regardless of the excuse.

It's a lot better than keeping them dead..........from both a moral and an economic perspective. I don't take moral responsibility for sudden changes in ambient temperature - I just try to manage the outcome.

What is needed is the correct species selection for your climate, harvest prior to temperature stress and/or summer and winter species crop selection. The only other option is the cost of environmental controls such as adequate heating or cooling. Anything otherwise is cruel to say the least.

So, do I understand you to say that, if through circumstances we are unable to rear fish to their harvest size, we should kill them rather than attempt to rear them to a useful size in sub-optimal (or sub-lethal) conditions?

What's cruel to a fish is a matter of pure conjecture. If we were able to ask them, they might choose discomfort over death - no-one really knows.

In any case (as I stated), I had a problem with temperatures which resulted in the death (at the hands of a knife) of a single fish.

Prior to the next night (and a forecast temperature drop), I put heaters in the tank. The fish are now more comfortable.

Gary

[Crusty]

I am not going to argue semantics with you Gary. Review what I wrote if you do not understand.

[GaryD]

Hi Paul,

I understand what you wrote.......but understanding ought not be mistaken for agreement.

Gary

[Rew]

Just because you can keep fish "alive" in sub lethal environments, it does not make it morally correct regardless of the excuse.

Anyone else tired of being told what we can't or shouldn't do by these scientific types? Rather than look at the food on the plate, they prefer to see the lost potential of a perfectly good eating fish .

And now its morals? Sorry but I for one am not here to be lectured about what others consider moral.

Backyard fish production is not commercial aquaculture. Perhaps there are other places to preach.

[GaryD]

Hi Rew,

Both Crusty and Arachdog are well-meaning and have made a valuable contribution to this forum.

Like most people who have an aquaculture background, they struggle with the way that backyard aquaponicists do things because it is often outside of what they believe to be technically appropriate.

Crusty appears to be arrogant but his surname suggests that his directness (which overwhelms me frequently enough) is a cultural thing. People of Dutch (or similar) descent often say exactly what's on their minds without regard to tact or diplomacy. His healthy ego is also balanced out by considerable practical experience in aquaculture.

When it comes to aquaculture (and even aquaponics), they and I are more likely to agree than disagree........but they are still coming to grips with how to deal with backyarders.

I'm hopeful that, if they are willing to persist, we can all learn something.

Gary

[Rew]

Hi Gary,

I agree with what you said in your reply. Crusty and Attackdog both have contributed alot to our knowledge of fish farming.

For me the problem lies with the delivery. At some point most people will tire of the message when delivered in such a way.

I attended a backyard fish farming class here in Denver this spring. Unfortunately the professor was exactly like our biologist friends here. He spent most of the time telling us what wouldn't work. Then tried to sell us a filter that would have added one to two dollars per fish for the next 10 years. He just couldn't wrap his head around the concessions needed to be able to afford to raise just 50 or 100 fish. His answer to alot of technical questions were to call a professional for detailed info. (Spend alot more money ).

I would hate to see our scientific friends leave the forum. The info that is stored in those heads is great. I appreciate the willingness to share. Just get rubbed raw sometimes by the abrasiveness of the delivery.


REW

[GaryD]

Well said!

[GaryD]

Hi,

We processed the last of our barramundi this morning.

Keeping them at a safe temperature as we move deeper into winter was going to be an unwarranted expense.......and our little Jades are starting to grow quickly so it was time for the barra to make the trip to the freezer.

These fish are about 18 months old. They weathered last winter with modest applications of supplementary heating.

There were 13 barra and one lonely jade perch in the batch.

The fish ranged in weight from 720g to 960g.

Gary

[grassroots]

Hi Gary, was the Jade and the Barra the same age?
How much difference in weight was there between the two fish?
Just trying to get a handle on the growth rate of different fish, I've been told the silver perch is slightly slower growing than the Jade, would that be right?
Thanks
Col & Gwen

[GaryD]

Hi Folks,

Jades and barramundi will both normally grow out to plate size in a nine-month season.

Silver perch definitely grow more slowly than jade perch. Growing them in tanks will usually take a couple of seasons.

Gary