Pond Boss Forums GENERAL QUESTIONS Water chemistry how long to get alkalinity up after liming?

Ph had gotten to 6.4 and alkalinity and hardness registered o for both. Have washed at least 2 -3 tons of aglime into the pond over the last week. Ph all around the 2 acre pond is now reading 7.4-7.6 everywhere. Alkalinity on the side of the pond where I washed the lime in is now reading 40. But all around the rest of the pond it still reads zero. I am running Kasco aeriation with 3 diffusers 24 hours a day. How quick should alkalinity start to read in other areas of the pond? What about hardness? It still reads zero everywhere. Any advise?

I'm not really smart enough to answer but I would think that it would depend how fine the lime is . Mine was a gradual thing as it dissolved. 3 months to really se a dif

PH varies over the day/night so it changes all the time. Alkalinity and Hardness (while measured similarly in #s) are not the same. The more you can spread out the lime the faster you will get total coverage. It is the pond bottom dirt you are changing and by absorption the water. See this https://srac.tamu.edu/serveFactSheet/112

Any advice? Yep, keep it up, I added agg lime the same way, by washing it into the pond. The first time I checked the water after adding the lime I got a 9.5 pH, 100 alk and 45 ppm calcium. I add agg lime the same way today when I run well water when I want to keep the water levels up during the summer. Adding some horizontal water movement would help to mix the water if needed. I have not needed to do that but I would not be afraid to do it.

My guess is add more lime. I would think you would need 4-6 tons total, and hard to over do it with ag lime.

Update: have washed 3-4 tons of very fine gray aglime in the 2 acre pond with aeriation running 24 hours. Ph has gotton up in the middle of the day to 7.8-8.0 all around the pond. Alkalinity has gone from zero to 40 all around the pond. Clarity has increased about 5 inches more. Only thing... calcium or "hardness" still reads zero? What's up with that? Should I just be more patient?

Sounds good to me. read below

From SRAC noted above

Water hardness is important to fish culture and is a commonly reported aspect of water quality. It is a measure of the quantity of divalent ions (for this discussion, salts with two positive charges) such as calcium, magnesium and/or iron in water. Hardness can be a mixture of divalent salts; however, calcium and magnesium are the most common sources of water hardness. Hardness is traditionally measured by chemical titration. The hardness of a water sample is reported in milligrams per liter as calcium carbonate (mg/L CaCO3). Calcium carbonate hardness is a general term that indicates the total quantity of divalent salts present and does not specifically identify whether calcium, magnesium and/or some other divalent salt is causing water hardness. Hardness is commonly confused with alkalinity (the total concentration of base). The confusion relates to the term used to report both measures, mg/L CaCO3. If limestone is responsible for both hardness and alkalinity, the concentrations will be similar if not identical. However, where sodium bicarbonate (NaHCO3) is responsible for alkalinity it is possible to have low hardness and high alkalinity. Acidic, ground or well water can have low or high hardness and has little or no alkalinity. Calcium and magnesium are essential in the biological processes of fish (bone and scale formation, blood clotting and other metabolic reactions). Fish can absorb calcium and magnesium directly the water or from food. However, calcium is the most important environmental, divalent salt in fish culture water. The presence of free (ionic), calcium in culture water helps reduce the loss of other salts (e.g., sodium and potassium) from fish body fluids (i.e., blood). Sodium and potassium are the most important salts in fish blood and are critical for normal heart, nerve and muscle function. Research has shown that environmental calcium is also required to re-absorb these lost salts. In low calcium water, fish can lose (leak) substantial quantities of sodium and potassium into the water.

My guess.....Do it again !

Wait for a while and monitor.