The main ingredient of any water feature is of course, the water. However, there are things that need to be added to the water to keep it healthy, clear, and optimum for the feature, flora or fauna.
Conditioners: When adding water to your pond, be it well water or tap water, this water may not be fit for your pond or water feature until it is conditioned. The water may be “hard” containing harsh minerals that could damage equipment or hurt your fish. The local utility (or even your own well water system) could add chemicals to the water making it safe for drinking, but not safe for pond life or beneficial bacteria. There may even be contaminates such as heavy metals from the ground or plumbing that you want to neutralize. Enter water conditioners. Many of these products are meant to remove chlorine (a disinfectant) placed into the water supply to kill pathogens. Unfortunately, this chemical hurts fish and wildlife and kills beneficial bacteria. Whether it is tap or well water, you need to test it for pH, KH, and GH. Utility companies usually publish the water they provide you with many other aspects and details of the water. Well water should be professionally tested from time to time anyway for your own safety as well water may contain contaminates. In any case, depending on what is found, there are many solutions available to either neutralize, bond with or otherwise dissipate these unwanted chemicals from your water feature or pond through conditioning.
Clarifiers: You have conditioned your tap or well water, but after it “becomes” pond water, some people do not like what they see. Often times, ponds may contain muck, sludge, algae blooms, or tannins in great abundance which cause the water to turn colors. This coloring may be a symptom of a bigger issue, or it may not. For instance, goldfish and carp do not actually need the water to be clear as long as the water is healthy. However, many people desire crystal clear water and able to see those goldfish! Enter clarifiers – a group of chemicals, filters or devices meant to clear water. Much of the staining of water is really very small suspended debris in the water. Some of this is so small, you cannot see it with the naked eye – but exists in such quantities that overall you can see the effect and coloring. Chemical clarifiers most often work by clumping these individual pieces together until they become too heavy and sink out of suspension. Clarifying filtration is basically presenting a mesh that lets water pass but not the suspended debris. Very large charcoal filters do this quite well but need to be placed before biological filters (they will not remove the nitrates that the bacteria need). Charcoal will remove staining tannins from leaves or vegetation and condition as well (removes chlorine). Settling filters or pits are used to remove inorganic sludge from the water. If you have a pond or water feature that is susceptible to algae blooms, a UV clarifier is right for you. Tiny algae “seeds” that are only 3 microns in size pass in front of a UV lamp that kills it. The dead algae begin to break down and clump together with others, and then fall out of suspension. Lamps must be sized for gallons and flow. Be warned that they weaken over time and need to be replaced annually.
Dissolved Oxygen: It seems silly, but planning needs to include a way to get lots of oxygen into your water. Your fish, bacteria and other pond life need O2 to live. Further, water movement will deter mosquitoes from laying eggs in your water feature. “Spitter” statues or fountains that splash or move the surface is one way. A waterfall or stream emptying into the pond is another. Deep ponds need a way to get that oxygen to the bottom. Using mechanical aerator bubblers can do this. Another is a gravel filter that forces the oxygen at the surface down to the bottom. Marsh features are tougher as the water movement is slow or nearly still. Even so, you should still have a current and lots of plants to get the O2 levels up. NOTE: Elevation and ambient temperatures affect your water’s oxygen level baseline. The higher elevation your pond is and the warmer the water is (especially in summer), the less O2 your water can hold. Plan for this.
Previous Article: 10: Pond Basics – Filters
Next Article: 12: Pond Plumbing – Hydrodynamics