140 liter party ice box. It will hold the heat reasonably well over night. NOTE the silicone hose placed in the centre of the tank. I have the hose drawing so as to be able to keep dirt out of the system by placing a cotton glove finger filter over the inlet and an inverted plate over the top to prevent it floating up and drawing air.
100 metres of 1/2 inch PEX hose is loosely coiled in the sun.
30w 3 l/min diaphragm pump. The white plastic base is trivial.
The pump circulates the water through the PEX hose and goes into and out of the reservoir through the one hole.
The silicone hose fits snugly inside the garden hose to form a reasonable but not perfect seal. it then goes through 90 degrees and into the reservior about 18 inches to create effective scavenging in the body of the water mass.