Almost ashamed of myself.

[ollief9]

For my pond, I just got a plastic box, put the pump at the bottom, filled the box up with car sponges, put a few rocks on top (to prevent the sponges from floating), connected the pump to a waterfall, bravo. My pond is crystal clear, biologically balanced and I have achieved this with a filter which costed me less than £25.

 

[rdnelson99]

For my pond, I just got a plastic box, put the pump at the bottom, filled the box up with car sponges, put a few rocks on top (to prevent the sponges from floating), connected the pump to a waterfall, bravo. My pond is crystal clear, biologically balanced and I have achieved this with a filter which costed me less than £25.

Wow. Unfortunately in Georgia with the intense heat algae is a big problem. I have now tied my two ponds together and the larger water volume has really helped. Water is crystal clear.

Pumps from the pond withe the fish. Through the Pre filter, Ghent to the bio filter under pressure. From the bio filter it is gravity feed to the top of the cascading waterfall, to the fish-less pond with plants. Then I have gravity feed from that pond back to the first pond via burrows pipe.

I may be wrong but I think tying the second pond in did more good then the filters.

 

[emerald76]

If water is dirty from fish poo and food, then a filter will help. If its algae, then it is from light, water depth, and nutrients. You can buy pond tint. This changes the color spectrum of the water so algae has trouble growing. You could also use a uv filter. You could also do a water change and siphon out the dirty stuff. Just dont take too much water because the new water will likely kill the fish.

New water shouldn't kill fish if you treat it properly and that means dechlorinating it
Lots of water changes would help