Pond Cooling

[Asianbucketbrigade]

Hi all, I’m working on an aquaculture project that involves fish that require water on the temperate side, 70-75 degrees or lower, and I’m working with a large above ground plastic pond. I’m afraid that shade won’t be enough to keep the water below 75 degrees. Are there any SoCal pond keepers measuring their summer temperatures and if so;
What’s the highest temperature you’ve observed your pond reaching and are there any low energy methods for keeping the temp down?

I’m talking summer highs of 105 or more degrees, and mid 80 degree lows at night.

Thank you!

 

[duanes]

I live in Panama (where air temps are constantly around 90'F), keep fish outside and one of the ways I keep the sun from heating water is by using lots of water lilies and other plants that deflect the direct sun, off the waters surface, like water lettuce and salvinia.

View attachment IMG_0187.jpeg

 

[jjohnwm]

Where I live we get air temps over 86F (30C) only rarely, and for relatively short periods. To us, 86F is hot.

But, a stock tank coloured a light blue colour, sitting in full sun, can often exceed 94F by day's end. A black tank feels even warmer.

Full shade throughout the day is critical; even in the shade, there is sufficient light intensity outdoors to grow most plants luxuriously. I have an outdoor dug pond that has begun to be shaded by a nearby tree; water lilies and other plants still flourish, but the lily in that shaded corner only blooms occasionally.

If I provide shade by means of some sort of semi-portable structure, removing that shade late in the season allows the sun to warm my stock tanks and extend the time I can leave my fish outdoors by a few weeks, but I need to cover the tanks at night to retain the day's heat as night time temperatures drop. Doesn't sound like that will be a concern for you.

 

[thebiggerthebetter]

Digging the pond into the ground may be considered. Otherwise high speed fans blowing on the surface and on filter output may drop temp by 3-5F in our experience. Shade. Insulation + chiller. Indoors / garage with AC.