Warm Water Trout

[Neal Westwood]

When I started my search for the perfect Aquaponic fish, trout was ruled out early because they like such cold waters. However, I have since proven that all is not lost.

 

My first year, I started with blue gill and hybrid stripped bass, all which like warmer waters.   My blue gill did not grow well, probable because they were in the same tank with the bass (and later with rainbow trout).  The hybrid stripped bass grew well and are good eating, but sensitive to handling and just about everything.  Every time I would net a few when they were under 9-10" some would come up sick or belly up the next day.  Once they got past that stage they were hardy and did fine.

 

As the first summer came to a close and water temperatures settled down to around 68 degrees, I added some 5-6" rainbow trout.  Being concerned about their sensitivity to heat and oxygen, I added a second air pump.  My water heater keeps the tank temperatures at 68 or above, as the tomatoes don't set fruit if it gets below that.  I raised trout along with the others all that first winter with zero losses in the trout.  We ate a few of everything along the way.  As spring rolled around, there were still plenty of trout in the system.  Summer brought tank temperatures of 74-76 degrees, and the trout continued to eat and not have any losses.  Finally by that fall, we harvested all the remaining fish, including the trout.  They were beautiful, 2-21/2 pounds.  Trout yielded the most meat per pound of the 3 fish. 

 

I had decided that I would go 100% trout as they are the easiest and cheapest to stock, with a fish hatchery just 45 min. from my house.  In order to eliminate a slug and snail problem, I sterilized my system and restarted it just a few months ago, and with the heat of summer in full swing, restocked my system with110  3-5" rainbow trout fingerlings.  (we did take 2 hrs to slowly acclimatize them to the higher temperate before adding them to the system.) We lost no fish in the transfer (except for a couple that jumped out of the tank!), and have had no losses since.  The tank temperatures routinely get to 76 degrees in the day, sometimes 78.  The fish will eat better when its colder, but they still eat strong.

 

Some say that I must have a hardy strain, and maybe I do.  I know the natural springs they grew in are in the sub 60 degree range, but they are doing well and have done well in the summer heat of my system.  I thought this might be helpful to other growers who discard trout as a viable year round species, but should reconsider.

 

Here is a short video of them feeding in 76 degree water.

 

Rainbow Trout in Aquaponics higher temperatures

 

Neal Westwood

UrbanAquaponics

[David Waite]

Man this is encouraging. I have been curious about this because brown trout are more resistant to high water temps. I love trout and will give them a try based on this . Ye ha.

[Jeffrey Walls]

Been raising trout in my system for roughly five years now. Rainbows the  the first year and a half or so, then brookies since. I have had rearing tank temps reach the 80s in my greenhouse. I had losses early but it was due to a growbed pump malfunction and I lost my aeration while at 84F. They did very well in the smoker however...:-)

I think the brookies are a bit tougher.

The trout I have now have seen just about the worst that could be thrown at them. I am hoping to breed them this fall and see if I can come up with a more aquaponic-friendly strain of brookie.

[David Waite]

Jeff never thought of brookies. Great concept, keep us posted on the breeding. You really need a few pics of your set up so we can give you some grief hehe.

Jeffrey Walls said:

Been raising trout in my system for roughly five years now. Rainbows the  the first year and a half or so, then brookies since. I have had rearing tank temps reach the 80s in my greenhouse. I had losses early but it was due to a growbed pump malfunction and I lost my aeration while at 84F. They did very well in the smoker however...:-)

I think the brookies are a bit tougher.

The trout I have now have seen just about the worst that could be thrown at them. I am hoping to breed them this fall and see if I can come up with a more aquaponic-friendly strain of brookie.

[matthew ferrell]

We grow a bunch of trout here.  While one poster is correct colder water does allow for more oxygen to dissolve in the water, it is the percent saturation that water is for keeping growth and stress low.  60% saturation seems to be the magic number for low stress and fastest growth.  

 

Also true that in most cases warmer water does lend to faster growth, but only to a point.  Trout grow fastest at 65 degrees.  Any warmer or cooler the fish has more maintenance cost, and therefore less energy in turned into flesh. 

As to temperature resistant fish, the Case-Western strain is supposed to be a "warm water trout". 

I am not sure why trout would get more parasites at low temperatures.  Logically they prefer lower temperatures, and therefore stress should be lower.  When you lower the amount of stress on an animal then you also lower the chances of pathogen or parasite to causing a negative impact.  Realistically all of the fish you have in any tank have either a parasite or pathogen such as Trichodina and Aeromonas hydrophila, or likely both.  

  

As for something we might try here are the golden trout.  These fish seem to be rather bullet proof.  When everything else is going wrong, these guys just keep on eating.

[matthew ferrell]

Birds and inverts are the two main vectors for parasites.  Mammals tend just to kill the fish themselves.