So simple usb water cooled gel mat for bed using basic materials found in the home or purchased online.

Ideal way keep cool avoiding sensory overload, on a very hot day or night, also helpful suffer from leg pain from over exhaustion from walking health conditions.

Found no issues with condensation

Supplies

10mm aqua Fish tank clear pipe 2 to 3 metres
USB mini water pump
Role of double sided carpet tape and duct tape
2 large Gel matts, I used 60cm x 90cm
Differant sized of Cereal storage containers that come as a set.
Foil lined freezer shopping bag.
2 freezer blocks wide neck drinks bottle
1 USB power bank.
Water
1 plastic sports drink bottle With wide neck accommodate water pump.

Step 1: Gel Mat

2 Gel mats sandwiched together with the pipe coiled between, not crossing each other, taped down by using duct tape, or using double sided carpet tape make more permanent , want ever to hand. Also consider where the two pipes leave the blanket back towards the container, could be at the bottom or side of you bed how you want it. The two pipes taped together using blue tape in this case.

Step 2: External Water Cooling Source

Take the smaller Cereal Container and place it into the biggest container from the set, while doing that use the freezer bag lining cut out of the bag stuffed between both containers. Cut a round hole in the lid of the biggest container to accommodate the two pipes from gel mat and the USB cable.

From the picture can see how everything is orginanised with 2 cold packs, the internal water supply for the water pump suing a drink bottle with wide lid.

Step 3: Internal Water Cooling Source.

The gel mat pipes is powered by water from the sport drink bottle which houses the small USB Water pump is within and the two pipes from the gel mat. (with its own water supply) That don’t have change water for gel mat every-time change the ice blocks as separate supplies.

it is just a matter cutting a hole in the drinks bottle top and feeding 2 pipes, and the Water pump cable through, that all within the bottle as pictured.

I found if the pipe is too small to push fit into the water pump, heating the pipe up can help, but dependant on size of pipe. The return pipe just hangs within the drink bottle taped to the water Pump supply.

Step 4: Controlling Temperature of Gel Mat.

Controlling the water level between the drinks bottle and the freezer block or how many ice block u use, it’s possible to control coldness of the gel mat to limited degree. Options of adding a electronic timer to the USB water pump that controls water rate over period of time could be a better option, but will keep posted in time.Adding something that can insulate the freezer block is also another option. But will keep everybody posted what works further experiment. :-)