Hey guys I'm new here. I have a 2.6 acre pond that varies in depth from 3 to 12 ft. Average depth is around 5 to 6 ft. I just purchased the land a couple years ago and have been working on creating my ideal fishery. I am currently trying to get the water quality correct. Below ar my current water test results.

Conductivity 24
Alkalinity 17.1
PH 6.83
Redox potential 171

I would like to get the alkalinity up and also clear the water quality up some. My question is, is it OK to add ag lime to raise the alkalinity and gypsum to clear up the water at the same time. If so in what quantities should I add them.

Also if it means anything. I have a 1 hp fountain aerator in the center pond installed about a year ago and 3 diffusers in the pond powered by a 1hp compressor that was installed yesterday.

Thanks in advance for any help. I am new to this and would appreciate a pros opinion.

MChandler, welcome, I am no expert, they will be along shortly, but I would see no problem adding both at the same time. The agg lime will raise the pH and the alkalinity. The Gyp will increase the calcium and will flocculate the colloidal suspended solids, and should clear up the water some, but it depends on what is causing the water to cloud up. Is it caused by water run off picking up clays and collecting them in the pond ? Or is it fish stirring up the clays off the bottom of the pond? And I would suggest you add all chemicals slowly and monitor such things and add AS NEEDED slowly

Tracy

Tracy,
Thanks for the info. I believe the sediment is coming from runoff. Back in the spring I cleaned up about 300 foot of shore line with the excavator and grass is just starting to grow on the exposed clay. Can anybody give me the amount of agricultural lime and gypsum to add.

Maybe I should make another post in a different category but I figure I would put it here since all of my information about the pond is already posted on this thread. Today i foumd 2 dead bluegill floating. The first i have had in the 2 years i have had the property.My first assumption was dissolved oxygen I was already informed of it being low in the spring when I had it tested and yesterday I installed 3 aeration diffusers. I added one large bass from a nearby lake a couple of weeks ago but there has been no issues since then to lead me to believe but that is the reason. I also just added a sand beach. I laid down 6 mil plastic on the bank and continued it about 20 foot into the water. Then I covered the plastic with about 6 inches of river sand. When adding the sand to the water Brown bubbles appeared and have been floating around since then which has only been about 3 days. Also while I was spreading the sand I had a hydraulic line bust on a piece of equipment causing a very small amount of hydraulic fluid to get on the bank and sand and go into the pond worst case maybe a pint in the water. But by reading other posts on here about oil in the pond it seems that should not be an issue and it has disappeared by now.

My guess on the blue gill floating up would be the aerator getting fired up or even the sand beach work. They tend to get worked up or stressed easy and if weak to begin with will just flip over on you.

Your alkalinity is low. I am blessed here with good water and good soil. Its nice to have 150-200 alkalinity. 20#'s per acre of hydrated lime will do the trick for you but you need to add this slow or you will see more floaters.

If it was me I would try to get my hands on 50#s of alum and 100#'s of hydrated lime then 20#'s of sodium bicarbonate. Mix the alum and lime together in a bucket then pump or throw it into the pond. With good aeration current it will push it though out the pond in an afternoon.

Leave this for about a week then put in the sodium bicarbonate. This will balance the PH and any free acids (alum) or bases (lime) and clear the pond nicely. The only reason I would say to add this is if there is iron in your sand and not just quarts silica. The brown bubbles has me thinking this.

If this was my pond this is what I would be doing.

Cheers Don.

Don,
Thank you for the info. I didn't even think about stressing them out. No more floaters since my last post. I will check again tomorrow. Yes my alkalinity is really low and I'm sure it has always bean that way since I have not done anything to the pond before testing it the first time. My land is nothing but red clay with maybe a half inch of topsoil then grass.

I have never dealt with adding any chemicals to a pond so I am kind of ignorant as of to what these are and what they do. (Alum, sodium bicarbonate and hydrated lime)

I was told to add 1 to 2 tons of ag lime for the alkalinity and found it cheap locally. And my neighbor has a friend that got 15 tons of gypsum for his pond and only needed 2 5 gallon buckets to clear his up and he is selling the rest at a good price. I will check the availability of the products you recommended next week.

Also you said it may sound like there is iron in my sand. If so what will that do to the water quality?


Thanks again for your help.

Mixing Alum and Hydrated Lime together creates a nasty, thick pudding that will not spray at all, and will also not mix into the water column...Create slurries, and spray the two chemicals seperately...

Haa ha ha yep been there. Yes alum has a hard time just dissolving alone. It is best to mix up the alum than the hydrated lime right after same day. Thanks for the correction.




#20 of hydrated lime is just about equal to 1 tone of ag lime. The only reason I do not like gypsum is all the sulfur in it. It is cheap and easy to get but will be clumpy. The finer the product the better it will flock.

I expect if there is iron in your sand it will go through an oxidizing phase for a year or so and basically be gone. In the mean time it can make the water brown. Iron can be toxic to plants quite easy but I am not sure how it will effect fish. I expect you would have to have tones that turn into alga. Most will be tied up with the alkalinity and should sink to the bottom and stay there. If only if there is iron in the sand keeping the PH up will work wonders.

Take some and put it in a pie plate. Then add a bit of water and vinegar leave it in the sun. Should oxidize over night.

Cheers Don.

Dono, I'm not sure what is meant when saying the #20 pounds of Hydrated Lime equates to a ton of Ag Lime...?

If that means the average immediate release of Calcium into the water, I can see that single aspect of comparison. There is however, a very real danger of killing fish in a pond using Hydrated Lime, plus the "Long Term" effectiveness of Hydrated Lime for raising alkalinity, "hardness" and raising pH is about 2 weeks in a typical vegetated BOW, where Ag Lime has an effectiveness, often measured in years. Ag Lime also poses almost no danger in killing fish, adds far more critical minerals and trace elements to the water.

Rainman,
Thanks for the info. So it sounds like you would recommend using ag lime? Is the 2 tons per acre a good amount to start with if so? Also would there be an issue adding gypsum with it to clear the water up and if so how much?

Thanks.

Yes there is about #20's of direct response from ag lime. Ag lime needs to have its bond broken in order to activate. The finer the mesh the more response.

There is some but nothing worth noting in micro nutrients in ag lime. The only one and we have bumped heads on this is Magnesium. I really really do not like dolomite ag lime. When the PH of water solution is at 8.5 there is 40% mag and 30% calcium in the solution. Magnesium is as far as I am concerned a micro nutrient and will trick plants into thinking it is nitrogen. They will go very dark with red veins limiting nitrogen uptake.

MChandler try a bucket test with your pond water and gypsum. You will see you will need tones and tones of gypsum to completely clear your water. I am not fond of it because of the sulfur ratio to Calcium. Acid soil will react with gypsum and can make sulfuric acid H2So4. Gypsum can be a waste product from coal smoke stack scrubbers. Calcium carbonate is used to wash the smoke and the result is low sulfur smoke and cheap gypsum with high sulfur content. Remember the drywall from China that was eating the electrical boxes in new homes a few years back? Ya to much sulfuric acid still active in the drywall. Add some humidity and you have some hungry drywall.

With all due respect I understand one product may be cheaper and less active but knowing that you can use much much less taking your time to add will yield the same result with out waste products and much much less product and effort. Calcium carbonate and sodium bicarbonate are the best buffers for any water solution. There may be some present in Ag lime.

Cheers Don.

See this for info #s 460 ,464 & 4606 - start with 4606.

https://srac.tamu.edu/index.cfm/CategoryDetails/whichcategory/25/

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
from 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.


Ag lime is the best option. Sometimes it will help clear the water. I usually try that in situations like yours before I move on to other options.

Nobody commented on this for you. Fish mortality maybe well be tied to your introduction of aeration. If your pond has stratified with a thermocline in the warm summer, the water on the bottom has lost its O2. If the water column is suddenly turned over, the fish are now in low O2 water and may die if they can't find good water. There is a start-up procedure around somewhere. Something like... You run the aeration 30 min first day, 1 hr next day, etc. It starts things up slowly and fish are happier.

ewest great read. Lots to read there man. Thanks.

Sorry I haven't responded to your posts recently but between work and working on this pond my time has been limited. Thank you all for the info. It has helped out alot. I lost a total of four fish with in days of turning on aerator on so I am lead to believe that you were right Don and DNickolaus. I think it may have stressed them out since I turned the aerator on full blast from the start. I have lost no more since then.

Ewest,
Thanks for the reading material. I have learned a lot from it.

I decided to go with the ag lime. Today I finished spreading 6 tons of it. Boy was that work. I spread about 2 ton by hand before convincing myself to use the trash pump. I used a 100 ft X 20 ft piece of 6 mill plastic on a hill. Pumped water from the pond to the top of the plastic and dumped the lime below the discharged hose and the water took the lime down to the pond. It only took about an hour to do 4 tons this way. I should have tried that before spreading the 2 tons by hand that took me 3 evenings to do.

I do have a couple of questions. How long does it take for the ag lime to raise the alkalinity? Also what is the best way to check it? I have the test strips but I know that can't be the most accurate way.

Thanks for all your help.

What part of VA are you in?

I have the same water issues it sounds like as you in central VA. I barely register any alkalinity. My water started out blue green when the pond first filled last year. This year it turned brown green but good visibility. Do you have flow into your pond and if so, will adding the lime raise the alkalinity and keep it up for a while? I'd like to add lime to my pond but and wondering if the 10-20 GPM inflow will just flush it out.

Interplexr,

My pond is located in Nottoway Va. What part of the state are you in? The only flow in the pond is from runoff. It is about 18 inches low right not but the rains last week raised is about 4 inches. I just added the 6 tons of lime a couple weeks ago and have not seen any changes but I am checking with test strips which are probably not the most accurate way. I need to buy a test kit but am not sure what the best one is. What are you using to check yours.

Lime will start working immediately and increase over time until it maxs out and starts to decline.

You can get a total alkalinity test kit (drop counter) for under $ 50. I am not aware of any alkalinity test strips but they may exist.

Hatch sells a inexpensive kit.

Hot tub strips have Alkalinity on them.

MChandler,

I'm just outside of Lynchburg, VA. I have a small spring feeding the pond we built. It averages around 20-40GPM depending on the time of year so I've been wondering if I'm going to accomplish much adding lime or I'll just have to do it on some frequency. I use the API aquarium test kits for carbonate hardness.

If you have a small stream from the spring, you could add ag lime there, and in the pond for some real gain/benefits.

The question is not how much water comes in but rather how much leaves the pond.

In my case what flows in mostly flows out minus any seepage and evaporation losses. I let water out the top and bottom. Its been real dry and I didn't want the level to drop so right now I just let it overflow 100% So just dumping the ag lime up from the pond won't hurt anything or the wetland plants in the back of the pond?

This is what I do and it works great. Hardness is about right heading into the pond. Heavy rain events I will add hydrated lime about four pounds right where the inlet to the pond is from the creak.

Cheers Don.

interplexr, in your constant flow situation I'd suggest getting soil samples from several parts of your watershed, combining the soils and getting the combined sample tested to see how many tons of Ag Lime per acre it will take to bring pH to 7.4, then at least quadruple that rate. Spreading as much crushed Ag Lime as you can into the inflow of your pond so water flows over it, or even through it if aesthetics are not a major concern. I'd also Broadcast spread quite a bit into the pond directly, and try to double the application rate suggested on as much watershed as possible.

Ag Lime max's out pH at around 8.2-8.4, so to try answering your question about any plant harm isn't possible till knowing what plants are in question, and the pH tolerances they have. The pH, alkalinity and hardness will drop once entering the pond itself an diluting until/unless there becomes a saturation/balance of ag lime salts in the pond and inflow. If adding several inches of crushed Ag Lime to the stream bed as suggested, only plants that like an 8.0-8.4 pH range will grow. I'd estimate the Ag Lime would be effective in the stream at least 5 years, if adding a layer in the flow several inches (4-7") deep. That will of course depend on flow rates and the overall amount of ag lime used.

Ewest,
thanks for the info. I ordered the hach kit and got it in the other day. I tested the water and the 6 tons of lime raised the alkalinity from 17 to 35. I will be spreading lime on the surrounding land to help out too.

Nice work and thanks for the info. As you know 17 is marginal and 35 is a whole lot better. 200 is optimum but many of us can't get close to that due to soil conditions.

Our soil conditions allow us to have 180 readings as normal.

Different parts of the country are different!!

Soil can be very different even only a couple hundred yards away.

Just wanted to thank yall again and give an update. I got the alk to 35 then we got 6 inches of rain last week and it dropped down to 30. Went ahead and spread 15 tons of lime on surrounding land so hopefully the runoff will help raise alk now instead of lower it.

I also went to the pond yesterday and it was the clearest I have ever seen it. I could see the bottom in 4 ft of water. Not sure what did I it but I like it.

Cold temps often clear the water or it could be the lime. Keep up with what you see on paper or computer so you will have a time line with results.

Often the effects of new water will change. Alka may go down a bit then rebound after mixing.