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It's getting cold, should I keep feeding the trout?

I have a 1000 gal system, with the fish tank 3' in the ground within my hoop house. That being said there is no heat added to the structure so it's getting cold in there. The current water temperature is about 35 F - this is Canada eh!.

I have 9 Rainbow Trout each is about 8" long at the moment along with some gold fish that I can't seem to catch.

So my question is, should I keep feeding the tout at these low temps? Is there a cutoff temp when I should stop feeding them?

Thanks for your input

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Replies to This Discussion

Permalink Reply by Jeremiah Robinson on November 8, 2013 at 11:06am

People catch them ice fishing, I would guess they still eat. The question in my mind is whether the nitrosomous bacteria still work enough at that temp. to keep the chemistry safe.

Permalink Reply by Brian Rogers on November 8, 2013 at 1:23pm

I have trout too but not those low of temps. My $.02 says a big 'reduction' in feeding is called for at the lower metabolism temps, but not a "stop" feeding (unless called for by second factor-more below). At most I'd reduce it down bare minimum and let them determine what they can/can't take in and process in a short period (shorter than summer) and then find where food is left lingering and back it down just below that.

The second half of that coin is what Jeremiah mentioned, the water needs to be filtered somehow and kept clean. So if you determine feed amount, you may find that it's still too much fish waste to be processed safely by dormant bacteria in a timely manner due to temps. Maybe some sort of heat from a mulch/manure pile can be piped/recycled thru the system from a hose???

So I'm guessing it might be seen as the fishes appetite will be your stop/go sign. You're Ammonia/Nitrite/Nitrate levels will determine how much you can rev the engine.

Last thought would be to ensure that dissolved oxygen can happen in the tank and preventing the water from freezing solid, maybe by keeping water flowing actively. But that only works to a point on the temp scale... This is just the leading edge of winter, we got a lot more to go!

Permalink Reply by Bart on November 8, 2013 at 2:26pm

Thanks for the quick feedback guys, that kinda where I thought we would go. I'm going to proceed by feeding one pellet at a time and stop when they slow up eating - I can't believe anything would be hungry at these temps so these things amaze me.

To your point about filtering, my low stocking was intentional with this in mind but I will monitor regularly to see what happens. I guess if nitrites start to rise I will stop or reduce the feeding.

Another question, should I keep the aeration going in the tank or do you think that is just helping to cool the water temp? I keep wondering if they would be better off with the aeration off but not sure if the DO levels would be ok without it at these temp's??

Thanks again for the input.

Permalink Reply by Brian Rogers on November 8, 2013 at 3:58pm

Permalink Reply by Jim Fisk on November 8, 2013 at 5:15pm

Hey Bart, How about heating that hoop house with a wood stove? We are hitting about 25F tonight but my wood stove heats the air and the water (using a ss 1" pipe in the firebox.) I try not to let the water get below 50F as the bacteria and plants will go dormant or freeze to death. Here's a pic of my home made wood gasifier using cheap scrounge:And the ss coil inside:Keeps things pretty happy all winter.

Permalink Reply by Bart on November 8, 2013 at 6:20pm

This is definitely on my radar Jim, but not for a few years. I have too many other commitments for my time and money at the moment. Not sure I will do wood since I don't have a supply and the cost of natural gas here makes it hard to justify going with anything else when it comes to heating anything - I heat my 2000 sq ft house for just over $1000 per year and that includes hot water requirements. So you figure the bacteria are done at anything less then 50F? I'm pretty much SOL then - glad I only invested in 9 fish for this adventure LOL.

Jim Fisk said:

Hey Bart, How about heating that hoop house with a wood stove? We are hitting about 25F tonight but my wood stove heats the air and the water (using a ss 1" pipe in the firebox.) I try not to let the water get below 50F as the bacteria and plants will go dormant or freeze to death. Here's a pic of my home made wood gasifier using cheap scrounge:And the ss coil inside:Keeps things pretty happy all winter.