# Does Limestone really grow lots of algae in creeks?



## Biblegrove RR (Jan 4, 2008)

I do not have a scource for lots of good sized creek rock yet, but I do for Limestone from the local quarry. I was told by local landscaper not to use limestone because it will be GREEN covered in algae! Any truth to this or is he just wanting me to buy expensive pallet rock from him?


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## Dougald (Jan 2, 2008)

Algae will grow on most any rock if the conditions are right. Limestone is formed from sedimentary deposits and thus contain the nutrients which will promote algae growth. In that sense the landscaper is correct. However, I would expect granite, basalts or other igneous rocks to also sport substantial algal growth in your running streams.

A key ingredient to growing algae is for the water to be slightly basic ... and limestone of course is a natural buffering agent, much more so than other rock types. However, if you are not faced with substantial acid rain (downwind of coal fired power plants) then your water will likely be slightly basic anyway.

Perhaps the question should be asked ... why do you object to algae? It removes nitrogen compounds from the water in a natural manner. As long as the growth is controlled a bit and the water is not allowed to stagnate, green algae is healthy and necessary to the natural balance of your water.

Regards ... Doug


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## Biblegrove RR (Jan 4, 2008)

Thanks Doug, 

I have "basic" well water. I will have a very steep and high (6') waterfall, really don't want it to grow long hair like the Grinch.


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## Greg Stevens (Jan 3, 2008)

What Doug says is true. See the Fossil Rock thread for my reply on the subject of algae. It won't be a problem if treated correctly.


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## Madman (Jan 5, 2008)

I have that type of stringy algea growth in the spring. However, I keep it to a minimum by removing it . Then it seems to subside drastically during the summer. I leave some so that small fish can hide in it. Also, the goldfish love it as food.


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## Webber (Sep 4, 2008)

There are several ways to address algae. It depends on what else you're trying to accomplish. If you want to have fish in the water, you might select some fish that like to eat the algae. I would just scrape and trim the algae and leave everything else alone. But, if you don't care about fish or plants you might change the chemical composition of the water without necessarily going deep into costly or exotic chemicals. If the water is a closed loop system (recirculating the same water) then you can add a full box of table salt. Changing freshwater to saltwater tends to kill most plants and algae and it doesn't turn the water strange colors or cost a fortune. Your pumps should be able to handle it, but they will need to be washed with freshwater at the end of season.


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## Trains West (Oct 4, 2008)

if you use salt will it cause residue where it drys on the rocks and edges ?


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## Bill Swindell (Jan 2, 2008)

It probably would leave a residue. Since you are asking, I assume that you do not have fish. In that case, you can also put bleach in the water.


As far as string algae, you can put barley straw in the water or barley extract. They are supposed to kill string algae. Also,, there are chemicals that are specifically designed for eliminating string algae.


You might try putting some fast growing water plant in your system and then thinning it out. Every plant that you grow and then throw away eliminates some of the nitrogen in the water. That is what is feeding your algae.


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## Mik (Jan 2, 2008)

I like duckweed...it's almost scale... except you can't have duckweed and goldfish, all you get is fat goldfish.


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## Biblegrove RR (Jan 4, 2008)

Here is a shot of the stones I have easy access too...


http://1stclass.mylargescale.com/biblegroverr/Front%20yard/Limestone%20003.jpg



And here is a shot of the "creek rock" I thought I needed instead. Is it the same but just weathered?


http://1stclass.mylargescale.com/biblegroverr/Front%20yard/Limestone%20004.jpg


From Peter Bunce - moderator -- the photos which were much too large have been convereted to links.


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## Biblegrove RR (Jan 4, 2008)

wow, why are my pics so huge? Sorry! 


Personal message sent, and photos reduced to links - by Peter Bunce - moderator.


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## Dave F (Jan 2, 2008)

You need to reduce them to 640 x 480 prior to posting them....


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## Biblegrove RR (Jan 4, 2008)

like this? 











Hi, That is getting close, but that is still a bit large at 800 pixels wide, the width limit is 640, but thanks for a quick change, see my note direct to you. Peter Bunce moderator, in England.


Algae here in the UK is a short term thing and it depends on certain conditions (light and temperature mainly) an then in almost still water. If younhave a quck moving stream that may not have any, but a local to you Garden center shoulb be ablle to assist, if it shows up. Wait till then amnd it can be quickly dealt with by chemicals, or even lifting it out of the pond by twiddling it round a cane, it is a stringy sort of stuff, and dumping it in the compost bin.


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## Dave F (Jan 2, 2008)

Limestone in and of itself will not "grow algae".. It's not a seed. It is however a great substrate for algae to grow on. You need a "starter colony" of algae to begin with though. If you have clean rocks and a clean (sterile) streambed then you'll have no algae growth. 

So, good news.. the use of limestone rocks will not "cause" the growth of algae. 

Now, bad news.. Your neck of the woods (soon to be Our neck as well) is rife with various forms of algal colonies.. Ever wonder why Little Grassy and Devils Kitchen have that pretty irridescent green hue to the water.... Yup... algae.. No matter what you use with regards to substrate in your streambed, algae will grow. Limestone has lots of nifty nooks and crannies for them to hold on to and grow inside of.. A smoother stone will still support algae growth, maybe not as much though. 

I'd not worry too much about the type of stone used in your stream and seriously look at other algae mitigation steps as outlined above.... higher flow rates, pH ballance, halogenation (chlorine, bromine, etc). Some species of fish will feed on the algae and keep it in check as well.. 

There's lots of options, just build it and have fun.


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## Biblegrove RR (Jan 4, 2008)

http://1stclass.mylargescale.com/biblegroverr/Front%20yard/Limestone.jpg

or










Hey Dave, when and where are you moving back to S.I.?


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## Dave F (Jan 2, 2008)

We'll be out here another 5 years or so, Gotta get my daughter through college. We're looking to head back there spring/summer 2013. 

I'm looking at a 27 acre parcel in Makanda right now. If I come back to walk the property and make an offer, I'll give you a call.


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## markperr (Jan 7, 2008)

You mentioned that you are on well water. What is the composition of the water pre-softened? Mine is high in iron and manganese. If yours is the same, you are going to have other problems to deal with, as in, your water will be brown and unappealing. 

I too am on well water and I fill and top off my pond with water from after my water softener. It adds a level of salt into the water which is far below the levels that would kill plants, but there is enough to help keep your fish healthy. Added benefit, your water stays clear. the other day I received a bit of advice from another neighbor who owns a pond full of Koi saying to keep the salt level slightly higher than normal. It'll keep the fish healthy. When I asked her about plants, she said that if the plants can't tolerate the salt, then they don't belong in her pond. She has loads of cattails and grasses and lily pads. 

Also, if you don't have good cover over your pond, the algae will bloom and turn your pond green. I've used algaecides in the past but they are temporary fixes. This spring I put a UV filter in line between my pump and waterfall and the water, which was pea green, turned crystal clear in a matter of about four days.


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## Biblegrove RR (Jan 4, 2008)

All I have is swimming pool test strips so here is what I got...

pH HIGH 7.8-8.4
ppm free chlorine LOW 0
ppm total Alkalinity HIGH 180
ppm Stabalizer IDEAL 30-50

I also have to figure out what size pump I will need and how to keep enough water in the pond to flow and not overflow if it shuts off etc.?


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## pimanjc (Jan 2, 2008)

Here you can see the alge growing on limestone.










JimC.


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## rgolding (Jan 2, 2008)

Jan found a blue dye at Lowe's that is supppose to keep the algae down. Worked pretty good by coloring the water and keeping the sun from penetrating so far into the water.


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## toddalin (Jan 4, 2008)

Of course the obvious answer (I don't think anyone's mentioned it), is to not leave water in the lake when you are not using it. My sprinkers come on and put water in my lake twice a day, but a float switch connected to the pump drains it each time. A valve routes the water either to the head of the river, or down the front slope of the yard. It also keeps it from overflowing during rains.


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## Matt Vogt (Jan 2, 2008)

If you don't have fish, by far the best solution for my pool has been copper algaecide. It lasts for quite a while. I usually only add it twice a season, which makes it much easier for the chlorine to maintain it.


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## Biblegrove RR (Jan 4, 2008)

ok, jury is still out on the Limestone I guess. I have another question concerning how to "seal" the river bed? Just cover it with rocks and then fill cracks with that spray foam... How about getting the water to flow over flat slabs of stone for waterfall? How do you keep water from runing off the sides etc? 

thanks


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## toddalin (Jan 4, 2008)

Posted By Biblegrove RR on 12/03/2008 8:05 PM
ok, jury is still out on the Limestone I guess. I have another question concerning how to "seal" the river bed? Just cover it with rocks and then fill cracks with that spray foam... How about getting the water to flow over flat slabs of stone for waterfall? How do you keep water from runing off the sides etc? 

thanks

Dry Lock hydraulic cement. Also Dry Lock water-proofing paint/sealer to seal the concrete.


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## Biblegrove RR (Jan 4, 2008)

Thanks Todd, is it really called Hydraulic cement? I can't find it on their website...

Do you have any step by step "how-to" photos of your waterworks creation? 

thanks


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## Biblegrove RR (Jan 4, 2008)

This it? 

[url]http://1stclass.mylargescale.com/biblegroverr/Front%20yard/fastPlug.jpg[/b][/url]


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## toddalin (Jan 4, 2008)

Posted By Biblegrove RR on 12/04/2008 10:46 AM
Thanks Todd, is it really called Hydraulic cement? I can't find it on their website...

Do you have any step by step "how-to" photos of your waterworks creation? 

thanks





The sealer paint:










The hydraulic cement:










When I built the volcanos and lakes I took lots of pics (none are hosted on-line at this time). But I didn't get any pics of the slate waterfall installation. I kind of had my hands full, and they were very messy at the time.


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