Pond Boss Forums INTRO Questions & Observations Limestone Border

This is probably a dumb question but I'll ask anyway. I was planning on putting a limestone border around my pond to control some erosion problems I'm having and also to trap mulched up debris that washes into the pond when it rains. I was explaining this to a friend and he told me that if I do that the limestone may change the PH level of my water. I didn't think it would, but now that the thought is there, I have to ask. Will the limestone affect the PH of the water? Right the PH is 7.5

Limestone would have a slight affect on PH, but much, much smaller than an equal weight of aglime, due to the huge difference in surface area.

Anyone have before and after limestone PH measurements for an example?

I have used large chunks of limestone as rip rap (don't like the smaller stone as it looks too formal compared to landscaping igneous rock.) and I have seen no rise in the PH. I think it would have dissolve more to do so and it does not.

I say go for it.

kent, limestone away.....i would challenge you to measure pH before and after and find any difference at all, in fact, if there is any chemical perturbation at all, it would be beneficial IMHO.

if you ground up the limestone (like a 1/2-inch to minus aggregate), kept all of it below the water line, and had a natural pH of 4 or 5, you might see something then.

Limestone sheds 1/16 of an inch every 100 years if exposed to the elements. So no benefits unless the water was constantly running over stones and then into pond. Throwing limestones into water no changes. But limestone ground to pass through a #230 mesh screen sieve quite effective and will hang in water column

This is interesting. Left to its own my pond PH would never exceed 5.5. So I lime it often and can never get it above about 6.0. I've often thought that perhaps some crushed limestone around the edges might help. From what you guys are saying perhaps if I put a good layer of Ag lime around the edges where it would get washed over by runoff might help. What do you think?

Limestone comes in all densities , some hard some soft. So how much it dissolves is dependent on its density and the acidity of the water it is eroded by. While it may not make a measurable difference in pond alkalinity (measuring ph is to variable) it will help the crustaceans (shrimp , craws and scuds ) who feed on or near it with shell strength and formation (especially in acidic water).

bz, sounds like you have really acidic natural conditions, are you in a conifer belt?

if you have a local source of quarried limestone, call and ask for the 1/2-inch to minus (or just the minus if they screen it that fine). put around shallows and edges, cant hurt, could provide a good spawning substrate and possible localized pH affect - ewest raises great point that you might get a whole micro-ecosystem on it, provide diversity in small critter forage.

Limestone project complete, hauled and layed down 18 tons Sat. Thanks everyone for the advice.

Kent any pics ? BTW how is your back - that is a bunch of rocks.

Late arrival here. I had about 90 tons placed by a slinger truck over geotextile fabric. I think I only picked up 2 or 3 stray stones so I highly recommend this method over using your back. Now that it has been there for a couple of years it is still in good shape and the geotextile fabric is doing it's job keeping the stone separated from the underlying clay. I was unable to get any tilapia this year which previously kept everything clean so I've been treating with Cutrine liquid and every time I do the algae sinks and turns into a fuzzy grey mess covering the rocks. Any suggestions on how to remedy this problem? Would aeration help?

Ewest, the back's not in good shape!! It wasn't in good shape before I started. I used a T-200 Bobcat to haul the stone and tried to place it as best as I could. When you're dealing with rip - rap you still have to hand work some of it. My Grandson was a big help in doing the hardest part of the back work. The # 4 wasn't too bad, I was able to place most of it where I wanted it with the Bobcat, then hand rake it to knock down the high spots. I just hope it stops my erosion problems and filters out the mulched up debris that runs off into the pond.I will send some pics as soon as I take them and can figure out how to send them.

Ryan do you mean clean the rocks or stop FA ?

Kent I think it will work or at least help a lot.

Ewest, well, both. I understand that ultimately I need to get rid of the algae and that would cure my problem with the fuzzy rocks. I've been spraying the algae when it forms... should I be treating before it forms? I suppose it would take the same amount of chemicals either way so I guess I'm answering one question for myself. The other question is now that I already have the fuzzy rock problem (due to the dead FA), is there anything I can do, without too much labor, to get rid of the dead stuff. Will aeration really help break it down faster? My hangup on installing some sort of aerator is that it couldn't be used all the time due to my geothermal loop but I am willing to sacrifice some occasional inefficiency to clean up the bottom of the pond if it would work. Keep in mind the area I have a problem with is in the first 3-4' of depth along the edges of the pond.

Ryan I will let the aeration experts answer that part of your question. I have seen several opinions here on the subject and can find them if you don't get an answer.

On cleaning the rocks I can offer 2 options. One draw down the pond and use a pump and hose to wash them off. We do that with our beach. Another option that will work without drawing down the pond is to rent a pressure washer and an extension (depending on depth of rocks). That will allow you to get the end of the washer about 6in from the rocks. It will wash the dead FA off the rocks. It would need to be attached to a pump from the pond (not chlorinated water). I would assume you could also use one of the pool vac/brushes/sweeper. Not sure how much work that would be at your place.

Well, I guess the limestone didn't do what I intended it to do. After 2 days of torrential rains ( that's the only kind we get here in La. ) the pond is full of debris. The whole surface of the water is covered. The rip-rap did solve the erosion problem on the end of the pond, but the #4(that's the size they put alond railroad tracks) didn't stop the debris. It rained so hard that it completely washed the limestone into the pond in some areas. So I guess I spent $ 1,300.00 for nothing, and I still have to go home and try to skim the debris off the pond. If anyone has any suggestions I sure would appreciate it.

Kent can you post a pic ?

Ewest, I have a few pics of the pond and the damage the rain did, but I've tried every way I know to post them and can't seem to do it. Is there a simple way to do this? I've read some of the ways posted on the forum and either I don't understand or it doesn't work. Is there a method for computer challenged people like me to post pics??

Kent email a couple to me and I will post them.

Kent,

If you anticipate constant problems with debris entering your pond, consider a low dirt levee around it. You can force all the inflow into your pond to 1 or 2 points under or through the levee. It can be filtered through a large pile of limestone gravel. That's the way I built mine, and it works very well.

Ewest, the power washer sounds like a really good idea, I have a pretty big one I can borrow from work and I have well water so chlorine won't be a problem. I'll post when I actually try it.

Kent, it seems to me that #4 is pretty small. #2 or #1 would do a better job at staying in place. A grass strip would do wonders for filtering out debris. There is geotextile fabric available that allows the grass to grow through that can withstand whitewater-volumes of water. Bretski posted about it in the planning stages at his place for use in a swale. If you decide to add more limestone, seriously consider the geotextile underlayment and the slinger truck.

Ryan,I think you're right about the size of the limestone. I have 18 tons of rip-rap being delivered this sat. that I will use along the sides of the pond in place of the #4. If the water moves that I'm giving up!! Ewest, did you receive the pics yet? I sent them 2 days ago to your e-mail. I got a notice back saying it was too large for delivery during normal business hours and it would be sent later.

I'm thinking of doing the same thing when my pond is rebuilt. How much is the stone costing per ton? How much area is 18 tons covering?

Rob and Kent, I ended up placing around 90 tons around my 1/2 acre pond. I had it spread from the erosion line where the grass stopped growing out about 5' or 6'. It's about 5 to 6" deep. This was done in August of 2005 when my water level was low. I figured that placing it during the low water level would make it easier for the slinger truck operator to place it more uniformly. The cost for #2 limestone, hauling (about 40 miles) and placing was $15/ton, I spent under $1400 in all for my place. The geotextile fabric I used was free, left over from a highway project.

I know I'm beating this to death but get a slinger truck and use the geotextile fabric, you won't regret it.