Backyard Aquaponics
A place to discuss aquaponics

Hi all,

I am new to posting on this forum, but have spent many hours reading the wealth of information.

I have dug a 2000 lt + pond, and the fish hatchery assured me rainbow trout would survive the summer, so I put them in 2 days ago but since they have not eaten the pellets from the surface and I have had 3 die.

I think the dead ones were because I had the pump turned off for a few hours, which is now fixed, but I am worried about them not eating.

Does it just take a little while for them to get used to a new environment?
It's possible the pond has a lot of mosquito larvae etc.

Any suggestions would be appreciated.

Happy gardening, Marts

Don't worry too much about them not eating, I've found sometimes mine just aren't hungry and won't eat anything for a day or two, then they'll go crazy at the next feed.

Also, when I first got my trout they were a bit skittish and didn't feed unless I wasn't there.

Keep an eye on the water temps and parameters and gradually increase their feed if they seem like they are getting their appetite back. Hopefully you won't have any more deaths.

Thanks Azira,
Makes me feel a lot better.

It's not uncommon for fish to suffer some shock going into a new environment.

Marts7374 do you have any filtration hooked up on your pond?

Do you know the:- water temp, Ph, Ammonia, Nitrite, Nitrate?

Some photo's are always appreciated.

Make sure you have the FT well aerated in warmer weather, as warm water holds less Oxygen than cold water. What is your water temperature, and how much does it vary over the day? Measuring early morning and late afternoon will generally show how much variation there is over a day, too much is bad news for fish

If you don't mind me asking, what generally constitutes too much variation? Or what variation is considered 'safe' and what amount is getting dangerous?

Thanks for your suggestions, the water temp is usually about 16 degrees, I have dug a pond into the ground and there is a deep channel at the bottom where I think the fish are hanging out. But I still haven't seen a single fish even at feeding time, I'm starting to think the kookaburras have somehow got to them, although I don't see how I have a net over. Had anyone had this problem with shy trout?

My trout tend to hang out at the back of their tanks where it is darkest (and most likely coolest), and the fish in one tank wouldn't even feed unless I covered their tank back up and went away.

If there are fish around they might just be hiding where they are most comfortable and feel safest. If they are eating their food then they are probably still in there. A friend of mine has a big pond of goldfish and they will vanish for weeks on end if a bird comes close to the water, so if you have Kookaburras then they might just be spooked and hiding.

Have you tried hiding out of view from their tank and waiting quietly to see if they'll swim around if they think you're gone?

Are you using floating or sinking? If it's floating and they are too shy to come to the top, they might not have realised it's there?

Sorry, only just saw this, I don't seem to be receiving half the notifications I should be getting.

It no doubt varies hugely with fish species, but I think 1 degree per hour would be no good for some species- that could be over 10C range in a day. Carp/gold fish can handle big swings though. I think we have seen fish deaths reported on BYAP due to large diurnal temperature ranges, but they generally are not well documented. I've seen up to about 4C variation in a day (12 hours) in my system, and that is certainly safe for Rainbow Trout.

Also varies hugely with age/size.

The aquaculture texts I've read don't talk about what is a safe swing versus not a safe swing but they all say any swing is bad.

Commercial systems have better controls and don't mind spending the money to radically reduce swings if they don't eliminate them completely.

Short answer ....

Thanks for the response Gunagulla. I generally don't get more movement than a degree or two over the course of a day, but before I got the shadecloth up there was one hot day when it climbed up 4 degrees and it had me wondering if I should get concerned or not.

But yeah, you're right Stuart, there would be so many variables it's pretty hard to answer properly.

Anyway, hijack over, back to Marts7374's topic!

Are you using floating or sinking? If it's floating and they are too shy to come to the top, they might not have realised it's there?

I'm using floating food, might they may be starving if they don't know the food is there?

My fish don't eat when the ammonia creeps up

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I turn off the bubbles when I feed... otherwise they likely can't see any difference to those round things on the surface..
I throw the food in and give a rapid quiet tap on the tank with finger nails, in the hope they will associate the noise with food.. Fush are Fush.... every group has responded to the training so why not silvers.. (in my case)
And why not trout.. a friend tells me how his now consumed trout, smashed the food with a true frenzy..
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