I Insulated Fish Tank and Sump Tank IBCs

[Bradly]

For those curious (as I was before I did this)...

I put 2 layers of visqueen plastic and R-13 (3.5") insulation over the top of my in ground sump tank and then wrapped the underside and all 4 sides of my fish tank IBC with R-30 (9" attic type) roll insulation.  I covered all surfaces with plastic visqueen and tape to keep the fibreglass pieces away from any possibility of entering either tank.

 

But the great results:

Outside weather yesterday at my house was 70 degrees max.  At 6:30pm I measured the water temps and the fish tank was 62 degrees and the sump tank was 61 degrees.  At this time it was 52 degrees outside.

I closed the plywood lid and threw a harbor freight moving blanket over the plywood top (temporary blanket until I cover the plywood top with foam insulation).  I then shut off the water pump so that the water didn't circulate to the grow beds at all...but of course left my air pump on all night.  Note-I only have 2 8" koi in the fish tank.

 

This morning at 6:30  the outside temp was down to 43 degrees.  The water temps in both tanks had only dropped 2 degrees all night !!   (I'm leaving my butterfly koi outside for the winter in the fish tank so that my system will be ready to jumpstart on the cycleing for the spring time).

 

I also bought a "Watts Up" meter ($95)  to test how much electricity my 1700w (runs at 13.7  amps) 120v DIY stainless steel water heater element would cost to run.  Turns out that it will cost me .20 cents an hour at Tier one electrical rates.  So I figure with the insulation wrap on the tanks, and with the heater on for maybe 3 hours a day maybe I can keep the koi comfortable no problem.

 

I'll update the actual time use of the heater as well as the cost estimates when we get into middle of winter.

Hope this helps anyone curious about doing something like this.

[Bob Campbell]

We get freezing temperatures during the winter.  I run the pond pump 24/7 all year long.  I don't know how cold the water gets, but the stream freezes over .  My Koi have lived in this pond for about 7 years.

[Bradly]

That's good to know Bob, thanks much, I wasn't sure the lowest temps they can take.   

I'm preparing the system for the tilapia next year .  Monitoring cost to heat water etc...so that I can figure out optimum times to move the fish outside and then to figure fish harvest "latest date". 

I am amazed though I have to say, that it's been getting down to 42-45 every night in the high desert where I live...but the water is still 70 degrees at 7pm and by 7am the next morning it's only down to 68 degrees.  That tells me my heating costs for tilapia later won't be that bad with the tanks insulated against heat loss.

It's getting about time for me to start scouting up some baby tilapia for the inside aquarium to get them started growing for the spring.

Take care Bob

Bob Campbell said:

We get freezing temperatures during the winter.  I run the pond pump 24/7 all year long.  I don't know how cold the water gets, but the stream freezes over .  My Koi have lived in this pond for about 7 years.