DIY Solar Powered Pond Filter With Skimmer

I have a small pond. Professional filter systems are quite expensive. So I decided to build my own solar powered pond filter with skimmer. I kept the build simple with easily available items.

Supplies

Filter: 20 liter bucket, 20 liter lava rocks, 32mm/1 1/4" PVC pipe, 2x 90° elbow fitting, aerator

Skimmer: 5 liter bucket, pond plant basket, 1100gph bilge pumpe, 32mm/1 1/4" hose

Solar Power Systems: 2x 20W 12V solar panel, Solar charge controller, 3x 18650 battery,3s BMS,waterproof box

Step 1: Filter

First cut the PVC pipe. You need one piece the size of the 20 liter bucket's diameter and one piece the height of the bucket.
Connect the pipes with a 90° PVC elbow fitting. Put on one end a plug and on the other end another 90° elbow fitting. It should now look similar to a Z.
Drill holes in the PVC pipe with the plug. It will be on the bottom of the basket.
Put the assembled pipe in the basket and fill the basket with lava rocks.
You can install an optional aerator before the filter. It will help the bacteria to clean the water. Make sure, you install it in the right direction.

Step 2: Skimmer

Put the bilge pump into the 5 liter bucket.
Drill a hole for the pumps outflow.
Put the pump's outflow pipe through the hole. Put a short piece of PVC pipe on and fix it with tape to the bucket.
Attach one end of the hose to the PVC pipe and the other end to the filter
Use the pond plant basket as a filter screen on top of the bucket.

Step 3: Solar Power System

You can power the pump directly via the 12V solar panels. This makes the build even simpler.
Or, you can use a simple 3s Li-ion battery back. Use 3 18650 batteries in series, attach a BMS and put it in a watertight box.
Connect the battery pack to the solar charge controller.
Use the 12V power output of the controller to power the pump.
I included a switch to the power output to turn the pump on and off.