Copied this from a thread on another forum, its a few different posts combined.
I'll edit it but its a combination of multiple posts so there may be some odd looking bits.
I'm just about finished my last load of home reared trout so I thought now would be a good time to start a thread on how I do it.
I buy around 100 at a time at around 2 inches and grow them on for another 6 months or longer.
Well I say buy but the local fish farm often give me 100 or so free but they are fairly cheap to buy, i'll find out the prices.
After 6 months or so some of them will be getting to a good eating size 250g (8oz) similar to what you see for sale in the supermarkets at 12 months they will be around 500g, this is the peak growth period.
I eat them and give them away regularly at this stage to reduce the stocking load on the tanks meaning the remaining fish have more room and can grow a bit bigger.
I'm currently using two indoor tanks (800 litres and 1200 litres) but i'm looking at getting a large 2000 litre outdoor tank or possibly a 1000 litre IBC eventually.
I don't use a filter, currently the tanks have mains water flowing through them via a small jet which also aerates the water and an overflow which feeds the waste water into the garden which next year will be used to water the veg growing beds.
The tanks are also fed via the roof water collection system, when it rains and my collection tanks are full, any excess flows into the trout tanks then out the overflow system.
high oxygen levels are crucial for trout, especially when highly stocked and when they get bigger.
a 1lb trout will use lots more oxygen than 1lb of smaller trout.
Temperature is another crucial one, the warmer it gets, the less oxygen the water can hold and the fish can die, a water temperature of 25C will usually see fish starting to struggle and die.
I feed them on commercial trout pellets which is cheap compared to chicken feed etc but I've never actually worked out a costing for it (yet)
I use rainbow trout
i have a net to catch them with
I keep them in the front room, no tank lighting, they seem fine with that.
Anyone thinking of keeping them outside (or inside) will need to be careful of direct sunlight hitting them, the warmer the water is the less oxygen it can hold so ideally keep them out of the sun altogether.
I'll get some pics up as I go, tanks are empty just now.
Light won't be a problem, whether high or low, its the oxygen that's the killer.
If it gets really hot on the trout farms they don't feed the fish that day as the increased metabolisim of the fish when digesting the food uses even more oxygen and they start dying.Picked some trout up today.
Was quite a hot day and the trout were a bit bigger than I normally get so only took 50 instead of 100.
The higher the temperature the less oxygen the water can hold and the bigger the fish the more oxygen they need.
A 2lb fish needs a lot more oxygen than two 1lb fish.
These ones are about 7" long, usually I get them about 4"
Picked them up in a big plastic bucket with a small filter to aerate the water.
Filter is 240v and I run it off an inverter.
Water is brown due to the heavy rains here making the river that flows through the fish farm dirty.
Here's the setup in the tank, this tank is around 1000 litres.
The hose nozzle is fed from the mains and sprays a fine jet under high pressure just under the surface of the water.
The pipework behind the nozzle is two seperate overflow systems in case one fails or gets blocked. One works below the waterline, one above.
I also have the tank drilled at one end with three 2" outlets as another overlflow precaution. The last thing I want is water running into the tank with nowhere to go and it overflowing in the house.
The two fluval filters are filtering the water slightly but its mainly mechanical filtering, they won't be doing much in the way of biological filtering.
They are there mainly to aerate the water as back up to the mains water in case it ever goes off.
There is no substrate in the tank, so the fish waste just breaks up in the tank and liquifies in the current.
The water jets circulate the tank water and all the waste gathers below them.
The overflow is set about 1/2" from the bottom of the tank so any solid waste near it is drawn out.
Overflows run directly down the drain, although I am looking at using the water for the plants but it may need further biological filtering to convert it from mostly ammonia to nitrite and then to nitrates which the plants use.
I run the mains water into it for about 2 hours in the evening
I'll get some tank pics once the water clears
These fish at 7" would cost around 50p each and are probably around 9 or 10 months old.
Commercially they aim to have them at an eating size of around 1/2lb (230g) by 12 months.
Thats the most common market size but they will double their size to over 1lb (500g) in three months if kept longer.
I don't often take mine over 1lb due to the oxygen problems, otherwise this tank would only safely hold around 4 fish.
Although the last few I have in the tank will probably be well over 1lb.
Once they start reaching a decent eating size I start eating them, leaving more space and more importantly oxygen for the fish that remain.
The optimal temperature for growing trout is 15C although the oxygen saturation level in the water is already starting to drop at this point.
There is a third less oxygen capacity in water at 15C that there is at 10C.
A water temperature of 25C for trout is usually fatal because of this.
This is worth remembering if considering trout as part of an aquaponics/greenhouse setup, you would need small fish with a very low stocking density if aiming to keep them at higher temperatures.
Lowering the stocking density helps and I keep a lot less fish per water volume than do fish farms so I can afford to keep them that bit warmer to maximise the growth.
I keep most of them inside the house in fish tanks and very rarely use the heating so i'm usually around the 15C mark inside anyway
I don't have the space to breed my own although I have thought about trying it.
Trout reach sexual maturity around 4 years old but by this time they could be well in excess of 5lbs kept in these conditions, possibly more and would need even larger tanks.
Could be done with just a handful of adults but not here! (at least not yet)
They will occasionally breed naturally given the right conditions but normally its done manually by stripping the milt and eggs from the parents.
But then you need tanks for hatching eggs, the fry through various sizes etc etc
If I had a river or stream flowing through the garden I would do it and pens off different sections so the water flowed through.
I'm feeding them standard commercial trout pellets and the benefit with the clear tank is that you can see exactly when they've had enough to eat, compared to the trout farmer who is judging it by a measured amount or the fish's response.
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Topic: Trout growing (Read 4958 times)
