Pond Blog

What Is a Secchi Disk and What Can It Tell You About Your Pond?

What Is a Secchi Disk and What Can It Tell You About Your Pond?

What Is a Secchi Disk and What Can It Tell You About Your Pond? A Secchi disk is a 20-centimeter diameter instrument used to quantify water transparency by measuring light attenuation. In pond management, the resulting Secchi depth indicates the density of phytoplankton blooms and suspended solids. This measurement allows managers to calculate the photic zone, estimate trophic state indices,...

Read more →

How Temperature and pH Change Ammonia Toxicity in a Pond

How Temperature and pH Change Ammonia Toxicity in a Pond

1.0 ppm of ammonia in winter is a nuisance; in summer, it's a death sentence. Do you know the difference? Total Ammonia Nitrogen (TAN) is a lying number. To know if your fish are safe, you have to look at your pH and Temperature. As both go up, ammonia becomes significantly more toxic. Don't let the heatwave turn a minor...

Read more →

Nitrate in Ponds: Is It a Problem or Just Part of the Nitrogen Cycle?

Nitrate in Ponds: Is It a Problem or Just Part of the Nitrogen Cycle?

Nitrate in a pond is a secondary byproduct of the nitrogen cycle that becomes a problem when concentrations exceed 50 ppm, as it fuels opportunistic algae growth and causes chronic physiological stress in fish. While significantly less toxic than ammonia or nitrite, high nitrate levels indicate a biological imbalance where nutrient input exceeds the system's export capacity. In a well-managed...

Read more →

Nitrite in Ponds: The Often-Overlooked Threat to Fish

Nitrite in Ponds: The Often-Overlooked Threat to Fish

Nitrite in ponds is a toxic nitrogenous byproduct that triggers methemoglobinemia, a condition where the iron in a fish's hemoglobin is oxidized, preventing oxygen transport. To mitigate this threat, pond owners must maintain a functional biological filter and utilize chloride ions to competitively inhibit nitrite uptake at the gill lamellae. Maintaining a chloride-to-nitrite ratio of at least 10:1 provides an...

Read more →

Ammonia in Ponds: Where It Comes From and When It Becomes Dangerous

Ammonia in Ponds: Where It Comes From and When It Becomes Dangerous

Ammonia in ponds originates primarily from the metabolic excretion of fish through their gills and the microbial decomposition of organic matter, such as uneaten feed and decaying plant life. It becomes dangerous when concentrations exceed the system's biological filtration capacity or when high pH and temperature shift the chemical equilibrium toward un-ionized ammonia (NH3). This toxic form causes cellular damage...

Read more →

How Does Low Alkalinity Affect Pond Biology and Water Quality?

How Does Low Alkalinity Affect Pond Biology and Water Quality?

Low alkalinity directly destabilizes pond biology by depleting the carbonates required by nitrifying bacteria to process ammonia, which can lead to a catastrophic pH crash. Without sufficient buffering capacity, the acids produced during the nitrogen cycle accumulate, causing the pH to drop rapidly. This acidity halts biological filtration, stresses or kills fish, and disrupts the metabolic processes of nearly every...

Read more →