I'm in the 7.4-7.6 range depending on time of day. I guess I still need to do more research. The chemical applicators and farmers here don't use lime in the NW (very NW) corner of Kansas, go in the other direction normally. I can't even find lime within 200 miles of here. Locals keep telling me no on Lime and use soda ash.. I need to find out why Lime in particular, is recommended over Sodium Carb.. is it based on water PH only?? What I find in research shows in becomes active with the bottom compounds as well. Don't know how credible it is but KU study shows a graph that says PH above 7.2, Not to add any Lime. Apparently I'm just not finding the right data to tell me why 1 over the other. Not trying to be difficult here, I just need to understand.
Snipe, first off, if the "locals" are talking about using HYDRATED lime (Calcium Hydroxide), they are talking about adding it to soils, and yes, you'd be sorry you did...it would burn plants and kill them....HYDRATED lime is used with Alum to offset the acid created from Alum, NOT as any form of soil amendment!
Ag Lime and Hydrated lime are not remotely similar.
DOLOMITE AG lime is simply finely crushed limestone and is used in ponds for a few reasons. It adds the essential salts of Calcium and Magnesium for fish bone and scale growth. It stabilizes and reduces pH swings. it adds hardness, it can not raise pH above a very safe 8.2. It promotes nutrient uptake by O2 producing plants and helps create beneficial algae blooms...all these things reduce stress on fish while increasing growth rates and potentials. If you decide to apply alum yourself, USE Hydrated lime, regardless of your water/soil pH!!! A relatively rapid change in pH, up or down, will badly stress and potentially kill all your fish.Adding AG lime to soil or water will NEVER hurt or make you "sorry"...it just may not be needed in some areas, but it is NOT just for raising pH in a pond...(that's just an added benefit).
Ag lime is also readily available around KC and St Joe...I'm sure several co-ops around you have or can get Ag Lime, but again, Ag lime is NOT what is used with Alum! I know every Walmart or big box home store has all the pelletized Dolomite ag lime you'd ever want or need. Home Depot has, or can order Type S Hydrated Lime (lowest prices too), which is used for concrete...almost any concrete plant has countless tons of it on hand too.
FWIW, a pH of 7.4 is what fish blood runs....water of the same pH is the least stressful on fish and reduces the salt loss from gills and kidneys. A higher pH is better than a lower pH. A hardness and alkalinity (due to calcium and magnesium) over 20 but kept around 150ppm, is optimal.
I wonder who is telling you not to add lime to a pond....is their experience based on growing plants, or fish? There are myriad myths and ideas on what is needed for a pond. In my experiences, areas primarily used for farming and livestock could not care less about a pond used for primarily growing fish...the ponds in these areas are primarily just a water source, for irrigation and drinking by livestock....fish are just an afterthought for a lazy day.
