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Lotus in Bloom

Water Quality Issues

Clarity in a pond makes all the difference in the world between something you love or a labor of love. In order to keep our water clean and in balance, we need to understand water quality basics, preform
regular water testing and add appropriate treatments when needed & on a regular basis.

Clear Water doesn’t mean healthy water, per say……..What Can Help:
1. Provide some shade for your pond. Pond Plants or Shade Structures
2. Do Not Over Stock or Overfeed Fish.
3. Avoid Runoff- Bark, Soil.
4. Provide Regular Maintenance- clean filters, add treatments, Test your water regularly (see below).

Achieving crystal clear water in your pond may be a challenge.

Learn about the main water quality issues, testing your water and about the Nitrogen Cycle aka Water Balance- read more below.

3 Main Water Quality Issues:


1. Murky or Cloudy Water

Symptoms: Water that looks murky, cloudy or turbid with little or no visible pond bottom. Occurs for
many reasons: mud and Silt can get into your pond by landscape runoff, Mulch and Bark can leach dyes
or create excessive/unnatural tannins. Potted plants disturbed from playful koi or that fall over may cause bottom sediment.
Brown or “tea” colored water- has a brownish tint may be caused from excessive iron in your water or
excessive tannins from leaves from maples or oaks. This can also naturally happen if you add Barley
Products to your pond.

Solutions: Routine water changes or do a complete pond cleanout during April-September, weather
depending. Keep runoff out of ponds. Add sludge reducers and beneficial bacteria products as clarifiers
and to diminish waste. You may also need to increase filtration.


2. Foamy Water

Symptoms: Foam apparent on edges, may look like someone added “soap” to your pond. Usually this is 
not harmful to the fish if it is short lived. Foam is a result of organic nutrients breaking down- usually from uneaten fish food & waste- that causes foaming at the water’s surface.

Solutions: Routine partial water changes- 10-20% to dilute the nutrient level. You can also add
activated charcoal to the filtration system to absorb nutrients or add a “defoaming” product that
binds and neutralizes foam (this is quick fix, not a long term solution- do not rely solely on adding
“defoaming” treatments). I always like to tell people to add beneficial bacteria treatments to help
balance pond water quality and reduce organic nutrients that may be causing foam. Also avoid
overfeeding your fish and try to remove uneaten fish food.


3. "Green" Water

Symptoms: Water has a green appearance from a “bloom” of millions of microscopic algae that are free floating or 'suspended" in your pond water.

This can be unsightly and cause alarm. Don't worry, your fish are probably fine! Hot weather and a full sun site often causes algae to bloom.

New ponds or recently cleaned ponds may often have a bloom of algae when the weather turns warm.
Solutions: Increase your ponds filtration with plants, additional filtration system or add a UV sterilizer / clarifier. Adding algaecides will temporarily help, but if it is persistent other options should be applied. Algae is blooming off the excess nutrients and sunlight that penetrates the water surface. Follow up with regular beneficial bacteria &/or sludge treatments to keep nutrient levels low.


New Ponds: Test Weekly

Established Ponds: Test 1-2 times a month (more if preferred) April-November, weather depending

Ponds with Problems: Test Daily until issues are resolved
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