The main ingredient of the pond is water. The water’s clarity, oxygen, chemical balance and volume are key. Depending on the type of fish, wildlife and plants within will also determine how much you must fuss with it.
Losing Water: Routine evaporation, especially during the warmer months is normal. As water splashes down the waterfall, some water is splashed out of the pond very slowly. The water surface loses water vapor to the atmosphere especially when it is warm and dry out). Even surrounding plants suck water from the pond. However this amount of water lost in negligible (perhaps an inch or two in a week’s time). But, if substantial water (4” or more perhaps over the course of a day), then it’s a sign that water is leaking out of the pond. A clog in a spillway may be overflowing a component. Another reason could be caused by a mole digging or erosion around the perimeter of the pond causing a low spot where the water is running out. Lastly, it could be a tear in the liner (patch kits are available). Fill the pond and components to max and turn off the pumps for 24 hours. Check again for water loss (main pool: perimeter or liner; filter box: crack or drain valve not closed fully); otherwise waterfall course. Note: To prevent complete water loss, install pressure switches in submersible pump housing or in the main pool to turn off pumps automatically. Beware of always leaving your autofill valve "on". If so, pay attention to your water usage (using a meter). The autofill valve could be masking a leak by keeping the water topped off! Keep a weekly record of your water usage or use the valve in conjunction with a timer.
Adding Water: Use an auto-fill valve adjusted to shut off when it reaches full waterline. Or, if manually, set a timer for a short period based on your flow rate and pond volume. Depending on the overall size of your system, little or no treatment is needed for this small amount of water (otherwise add the prescribed amount of stress coat water conditioner which removes the chlorine and other chemicals added to tap water to make it safe for the flora and fauna). NOTE: If adding bacteria, always wait a day after adding fresh water.
Clearing the Water: The water should be clear enough to easily see the bottom of the pond. Should the water become cloudy or very dirty (such as when cleaning or disturbing the bottom), use the prescribed amount of clarifier. If after a few days, there’s still no noticeable improvement, it may mean the filters are dirty or clogged (check and clean as needed) or the pump is not running at optimum flow (ensure they are clear and bypass lines are fully closed). If algae blooms are at fault, use an algaecide. If still no luck, consider a large water change (25-50%). You will have to take care when replacing water with pond fish.
Monitoring the Water: There are a myriad of devices you should have to assist you in specific data about the water. Get a floating thermometer. This is key when deciding on winter shutdown (<40°), spring start-up (>50°) and seasonal feeding. At the freshwater fill line, get a water timer and meter to allow accurate measuring of water added. If during initial filling, you made a Staff Head Gauge, you will have an accurate pond volume by depth and time to fill or drain. Test kits will allow you to see composition.
Testing the Water: If the pond is operating at peak efficiency, the water will be clear; not cloudy or murky. Algae will cover nearly all surfaces; but not excessive amounts. The fish will be vibrant and active; not dull and lethargic. There should not be a buildup of debris on the bottom of the pond and what debris there is should be breaking down quickly. Aquatic plants should be thriving as well. However, if this is not the case OR you have just completed excessive cleaning or large water changes, use a 5-in-1 water test kit which checks the levels of pH (Free Hydrogen Ions), KH (Carbonates and Bicarbonates Ions), GH (General Hardness – free Calcium and Magnesium Ions), and of course NO2 (Nitrites) and NO3 (Nitrates). If you have a large fish population, test weekly. Keep test strips on hand and dry; avoid touching them. Note: One-step glass vial oxygen saturation tests are available (DO). Optimum: pH: 7 to 8.5, KH: >107*, GH: 107-446*, Ammonia: <0.1*, Nitrite: <0.1*, Nitrate: <50*, DO: >6* (*measured in ppm= parts per million).
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