Pond Boss Forums INTRO Questions & Observations Hydrated lime instead of Agg

My pond is 1.5 acre. I've added 5 tons of crushed gravel lime and 1500lbs of powdered garden Agg lime. My ph is between 5-6 but can't get it up any higher. I'm waiting to stock fish until I can get it between 7-8. My pond is surrounded by pine trees so most of the runoff is very acidic. Since I have no fish, could I add some hydrated lime to boost my ph quicker and would it stay at a higher level or just drop back down to 5 in a month or so?

Thanks in advance for the advice guys

Cav, the best route is to gather several soil samples around the pond and surrounding areas, mix then, then take them to your USDA office or other place to be tested. They will tell you how many tons of Ag lime is needed to reach a target pH. I suspect in the pine area you will need, at minimum, 10 tons or more per acre. Adding higher amounts won't hurt and can extend the time between applications. Spread about half in your pond, and the rest in as much of your watershed drainage area as possible. Ag lime does take a little time to work, but will work until acids dissolve it all (8-15 years) at proper application rates. Hydrated Lime is very different, it acts almost instantly, and is very short lived.

I would not suggest using Hydrated lime. You could still stock your fish and add the Ag lime without danger to the fish, since the Ag like changes the pH slowly.

Up here, Ag lime is short lived too, and usually needs to be applied every 2 years to the soil.

That's interesting. This is farm country and you rarely see a farmer applying lime down here. Is the soil there just naturally acidic or is it due to lots of pine trees? Do the unmanaged waters there such as ditches, ponds, etc. produce any decent fish? I know very little about how PH affects fish health and growth and am trying to learn. I saw a Pinpoint PH meter advertised and may get one just to check my ponds out of curiosity.

An Ag Lime test recommendation (like those the USDA gives) is usually to only amend soils for a single growing season. When I got an analysis per acre, I suggest multiplying that by 10 for longevity along with adding limestone rip-rap to all inflow channel areas as far upstream as practical. Ag lime tops out in raising pH at a very safe 8.2.

In a heavily pine tree filled watershed, the dropped needles are very acidic, so Ag Lime really can't be over-applied.

The dropped pine needles and sap are what leach into the soil making it acidic. The lower pH does affect fish growth, but mostly in an indirect manner. The acidic water will support far less phytoplankton, macrophytes and other tiny creatures/plants that make up the base of the food chain in the pond ecosystem. Less base means fewer fry growing to feed higher links in the food chain....

Multiplying it by 10 would have meant a lot of lime. I use A&L for the soil testing and their recommendation was 3,000# per acre. I'll test again next year to see how it changes things.

Check the alkalinity not ph. PH changes over the day. See this

https://srac.tamu.edu/index.cfm/getFactSheet/whichfactsheet/112/

Water is likely ok to stock many pond fish species.

See this

https://srac.tamu.edu/index.cfm/getFactSheet/whichfactsheet/262/

Let me clarify, that recommendation was for soil, not water.

Driving 30 miles to pick up 2 tons of powdered agg lime, same stuff farmers put on their soil, today. Then the fun begins... shoveling it in the pond.