Backyard Aquaponics
A place to discuss aquaponics

I had my first fingerling jump to it's death while I was away over the weekend, came home and it'd made it a few meters from the fish tank (cat might have helped, but there were no physical problems with it).

It has about a 30cm that it needed to jump to make it out, and I would have thought it'd be a little too high for them.

I've been planning on finishing off the lid for my tank for a while now (and finish off the how to video for the tank), so this will give me a little of a kick to get onto it. I was enjoying it without the lid, because I can see into it, and watch them swimming around, it won't be as easy with a big lid in the way

But how high have you guys seen the trout jump?

Certainly 20-30cm is within range for 10cm long fingerlings, in my experience.

Hey Colum, sorry about your jumper. Jayendra suggested tucking bird netting tightly across the top of the FT and down the sides between the IBC bladder and cage. I have used black bird netting which is not visually intrusive, you can feed the fish through it and it keeps the fish in and the leaves and birds out, and is easy to take off. You can also put a solid lid over it.

bird netting is not a good idea, i was warned off of that very early.

if they get thier head through the holes, they will hang themselves by thier gills on the way back down.

go for a lid, shade cloth, anything else with holes that your trout cant get thier head through.


Couldnt say how high they can jump, but the force they can jump with is amasing.

on my metal tanks, i had left a large lid when i cut the hole in the top.
i had fed them and one guy went for food that was under the lip, he hit the food so hard that he flew out of the water, smacked his head on the lip (1mm or so sheet metal) and gave himself brain damage, pretty much instant death..... his heart was still beating when i picked him out of the water, but he was gone.

Good point Yav I can just picture the poor little things hanging in the breeze
Just as well mine have fat enough heads now to not fit through the bird net!

I've got it set up for a wooden lid. All the hinges are concreted in, so I just need to weld in the supports, and I'm good to go.

I'd just been a little lazy. I might invest in some of those gas struts that they use in cars to keep the ute lids open.

I've found that I only lost a couple of jumpers within the first few weeks. After that they settle into their new surroundings.

Fish will only jump if stressed

Or going for food a bit too enthusiastically.

We're into our 3rd trout crop and have not had a fish leap out of the tank <75mm. I thing stocking density has a part in it.

I sure hope so. The last thing I want to do is cover my pond. If you look at fish in a lake they won't jump out. It must have to do with size of the water. I've built in ledges all around, so I hope they stay put.

The guys at the hatchery told me that they are more likely to jump following a flow of water into the tank. Was my experience last year when I found 2 on the ground right below my return outlet (and the only spot I had a small gap in my netting)

I like having the lid open on my tank, it's fun watching them swimming around, plus easier to keep an eye on them.

My mother in law was looking after them while the jumper went for a escape attempt...

I'm sure it had something to do with that

I've still got to finish off the tank though.

Not many members have their tanks covered. I only ever had about 4 or 5 jumpers over the 3 trout seasons I did. Faye stocked hundreds of trout over 7 or 8 years and I rarely read of her losing any. It will be fine.

I have bird netting over all my tanks and can only remember finding one that was gilled in it over all the years and with 1000's of trout in each tank. The advantage of the bird netting is you can still see the fish and feed them without having to lift off a lid.
Its possible for them to jump 40cm when at fingerling size and yes they definitely will mainly jump where the water flows in from the growbed.
The first night in their new home is the worst and I once had a customer who had 21 out of 25 fish jump out the first night!!
I myself once lost 230 trout when I left the netting off one of the tanks for just 2 hours!!