More About Pond Sludge, Viresco and General Questions

I would like to thank Kira for her questions My answers are in red...

Tony,

Thanks so much for your quick reply! I will try more Viresco next year( my guess is it does not work in freezing winter temperatures).

Like most bacterial products Viresco works better as temperature increases... however algae growth also reduces significantly as temperature drops also. If Viresco after period of weeks does not seem to be controlling algae then it is necessary to add more. Viresco works by removing nitrates... this takes time and a vable population of bacteria.

I test my water regularly. Other than being very hard and alkaline ( local phenomenon, we use water softener in the house)  it has always been fine.

Hard water is much better than soft water for a pond since it helps to keep pH under control. Hard water ponds do't have pH problems normally.

The bottom of the pond and the more shallow shelves are covered with gravel (small pebbles). Contractor has built the pond for us at the time when we knew nothing about ponds! It is Aquascape Biofalls design recommended by our Landscape Architect, who has a similar pond.

The bottom of a pond should never be covered with anything... debris accumulates, rots and removes oxygen from water. In extreme it can cause significant health problems for fish.

Removing all that gravel from 6,000 gal pond is not a task I relish...

What would you recommend putting on the bottom? Leaving the liner bare? That would look quite UGLY, especially in shallow parts, I would think.

Leave the liner bare.

I also have plants growing by themselves in the gravel, without soil, I do not fertilize them or grow them in containers, they seem to do just fine, they grow and bloom better than they did in containers with fertilizers. Is that wrong?

I suggest put the gravel inside planting crates or pots

I also had the question about the goldfish. I have not fed mine for three years, with rare exception, when I do it just for fun. They seem to do just fine other than blue herons and racoons eating them from time to time. Why does everyone( the books and experts) say I need to feed them? What am I missing?

People feed fish more their own enjoyment (pets) than the fish's needs. All ponds have a myriad of underwater life and fish feast on the items continuously. If you don't feed the fish they will grow much more slowly and will remain small probably. This is OK. Manufactirers of fish food like to sell more and more food of course.

My method (taught to me by my Landscape Architect) saves money on fish food and plant food, and lowers amounts of nitrogen by not introducing these substances in the first place. The only downside is cleaning the sludge from the gravel. Plus fish eat algae (I guess?) and plants consume nitrogen from water? 

Fish eat algae and creatures that hide in the algae. Plants are poor at removing nitrogen from water ... they get most of nutrients from planting medium.

This seems to be a lower maintenance method. Why doesn't anyone write about it, or am I missing something big?

What is the harm in sludge?

Main problem is unsightly appearance and the fact that organic sludge removes oxygen and creats opportunities for pathogenic bacteria to multiply.

Sorry to bug you, I have not been able to find straight answers to these questions!

Thank you so much! This is priceless to me!!! I love my pond, my fish and frogs :). Does YOUR book talk about these subjects?

My book covers everything you need to know to become a highly competent pond keeper and thus get maximum benefit from a pond. It does not cover fish themselves at any length ... only how to make sure your fish survive and thrive.

I am from Russia, but live in US permanently, and love gardening. We live on 4 acres of woods.

Kira