Barley! Does it really work?

[Waterbug]

I haven't been in a pond forum for many years and I'm surprised things like this still come up.

Many years ago there was a study done based on the beliefs of farmers that placing bales of straw into a pond would reduce string algae. The study was pretty inconclusive. There may have been a reduction in string algae but it's hard to say why, could have been completely unrelated to the straw. For sure it did not eliminate string algae. Even farmers never thought it would eliminate string algae.

Some enterprising retailer heard the farmer myth or read the study and a new business was born. The key to the business is most people can't buy cheap barley straw. With a 10x, 100x mark up it is a great business to be in. Every pond supplier is happy to sell you some. $10 for 5 cents of straw, super.

This product can really only be sold to new ponders, and only once. Therefore it doesn't really work to say it kills string algae as new ponds have single cell algae (green water). So to target new ponders sellers just drop the "string" and bam, it kills "algae". Being precise is bad for business.

Another nice touch is saying it takes 6-8weeks to clear a green pond. Guess how long many new ponds take to change from green to clearer? 6-8 weeks. So you get testimonials in pond chats saying it works, just playing the percentages. People like to be right and so adding the straw must have been the reason. When it doesn't work I think most people are too embarrassed to say anything.

The hydrogen peroxide (H2O2) angle was a nice touch and came later. It is true that H2O2 is naturally produced in organisms. It is also true that it will kill plants in high enough amounts. Skip over all the actual facts and it sounds like a pretty logical reason why straw would work. The facts skipped is there is nothing special about barley straw producing H2O2, or that the amounts produced are at the level of a fart (very small toot) in a hurricane.

And of course highly concentrated barley extract must be better. Has "barley" in the name after all. Profit margins are even better.

There are tons and tons, a never ending stream of things that will claim to clear your pond. None, except UV, will claim to be 100% effective and that's their con. Don't be bummed if you fall for one of these scams. But do me and all ponders a favor and get really, really pissed off at the stores ripping you off.

BTW, I've fallen for these types of scams so I'm not in an Ivory Tower.

 

[DrDave]

Thank you for your comments. I don't use either and my ponds are clear.

 

[DoDad]

I tried barley straw when I first started ponding. That didn't work so I tried barley pellets, they didn't work but made a nice mess.
Hydrogen Peroxide may kill your plants at a high dose(whatever a high dose is) but if it's that high I would think your fish would also be dead.
I have a 4200 gallon pond that's overstocked so I do have some Nitrates feed the plants and algae.
What do I use that will kill string algae but not kill my plants? Hydrogen Peroxide! I tried the .3 Hydrogen Peroxide and it took to many quarts at a time to kill string algae. Now I use Baquacil Oxidizer for swimming pools and it's .27 and does a very good job at killing string algae but has no effect on plants.

 

[bsr8129]

Argh so whats the conclusion here on getting a clear pond?? my pond is green and doesnt look to be going clear anytime soon, pump and filter have been running 24/7 for a month and a half now. I was going to try barley extract to see if that works but know i am more confused.

 

[DoDad]

Have you ever thought of using a UV?

 

[bsr8129]

ya i have thought about UV, but placement and cost are detering me, and i was hopeing to not have to go that route

 

[DrDave]

What doseage is safe for fish with Baquacil Oxidizer?

 

[DoDad]

I use one cup for every 2000 gallons. I also use a air pump to disperse it throughout the pond,

 

[chilligirl]

Argh so whats the conclusion here on getting a clear pond?? my pond is green and doesnt look to be going clear anytime soon, pump and filter have been running 24/7 for a month and a half now. I was going to try barley extract to see if that works but know i am more confused.

you need to out-compete the algae. In other words, get yourself some plants that are really good nutrient absorbers and that will provide some shade. Water lettuce and hyacinth are especially good.

Your filter won't do anything for green water, or for string algae really, as the filter won't remove nitrates from your pond, which is what plants and algae both use.

Plants and algae both need light, CO2, and nutrients. Provided there are adequate amounts of these, plants are actually better/more efficient at using the nutrients than algae is. So if you load up on plants, they will out-compete the algae.

My pond was very heavily planted all summer (will be again this summer, everything is already coming back), and as a result I had crystal clear water and a constant reading of no nitrates on my test kit, despite having fairly minimal filtration and a decent fish load.

Now with it being spring, water temps are cooler, I haven't got much in the way of shade yet (the tree by the pond is still bare, lilies have just come up, hyacinth not available to buy yet), so algae is winning for the moment, both green water and string algae. However once I get some hyacinth in there for shade and nutrient absorption and the rest of my plants wake up, I'm sure it'll clear right up again

 

[Waterbug]

Yes, what is the one thing to do for a clear pond? Trick question. There is no one thing because there is no one thing that clouds a pond.

A properly sized and maintained UV will kill all unicell algae (green water). It is the only thing that will 100% of the time in every pond. You also don't have to run it all the time. Once the green water is starting to clear you can choose to turn it off. The algae may start to come back or, surprise, surprise it may stay away for months. Running it all the time is fine, just not that great for your pocketbook or the planet.

However that is not the whole story. Algae goes through a life cycle and there are different species of algae. One thing some algae do is form colonies, clumps. These can become so large they can be seen with the naked eye, they can look brown, like pepper suspended in the water. These can become so numerous the water is not clear. UV will kill these, but not as fast since they are shielded. Protection from UV in sunlight is the theory as to why they form colonies. But even if dead these clumps still float around. Generally these have to be mechanically removed. There are chemical methods but they have pretty serious side effects.

There are many other things that cloud a pond too. Many have different methods of removal. Ponds are always changing so getting rid of one thing can lead to others. A ponder that expects a one thing fix or doesn't want to know the complexities is going very disappointed long term.

The idea that algae can be starved of light or nutrients has been around many years and it will be around many more. It is very easy to disprove but with such an appealing logic it is here to stay.

It is true that increasing the amount of light and nutrients will increase algae growth as algae grower do. But this is to get something that looks like green paint. Reducing light and nutrients will reduce growth but the complete removal is impossible in ponds. The depth of ponds requires very little algae to appear green so complete removal of all light or nutrients. Dyes for example reduce light and algae growth but also change the color of water to brown or red so you don't see the green.

For those interested the light test can be done with an indoor fish aquarium. Keep it in the darkest place in your home and don't use a light in the blue spectrum (plant light). Watch the algae bloom. Or check out any aquarium forum for people with an algae problem. The amount of blue spectrum light reaching the tank inside a home is extremely low. Algae need very little light.

Nutrients. The easiest test is to measure the nutrients in clear and green ponds. Generally a clear pond will have a higher nutrient level. Impossible? Adding plants to remove nutrients kind of ignores the fact that algae is a plant. When algae grow they take up nutrients. When they die those nutrients are released. You might also wonder how those nutrients make their way past those millions of algae to the roots of the higher plants.

Algae do die, they do have enemies. One enemy is a bacteria which releases an enzyme to break down the wall of algae so the bacteria can eat the inside.

A second enemy is string algae. At least some string algae produce allelopathic chemicals to kill unicell algae. This is a pretty common defense in the plant world. I have done many experiments with string algae and unicell algae and it is very interesting. In one case a hand full of string algae added to a 900 gal pond with green water cleared in about 5 days. In another experiment the string algae was killed by the unicell algae by appearing to coat it, but I couldn't really tell how. It seems both have weapons and defense. My guess on which win depends on where each was in the life cycle, species and other factors like bacteria.

I have heard of ponds with both green water and string algae but I have never personally seen one. While I think it must be possible it seems rare. I'm talking about green water not other materials in water that make it cloudy.

There was a guy about 10 years ago who did experiments (I forget his name, Merck?) with water from a pond that had been cleared of green water. He filled containers (if I remember this right) with 25%, 50%, 75% water from a green pond and filled the remaining amount with water from the cleared pond. The unicell algae died very quickly and in the amount corresponding to the amount of clear water added.

This may be why some ponds will stay clear after a UV is turned off. The UV kills algae which bursts their cell walls releasing the food that this specific bacteria needs so it grows releasing the enzyme which kills more algae.

Adding pond plants will almost always add string algae too. A person adds plants to remove nutrients to kill the algae and the water clears so the person must have been right. The string algae gets no credit. The next question the person has a month or two later...how do I get rid of string algae? No one makes the connection of how did the string algae grow if there were no nutrients, or for that matter, how do the plants keep growing? Single cell plants need a very small amount of nutrients and floating around in water gives them a good chance of finding those nutrients.

A stream will also clear green water sometimes because the shallow water allows string algae a chance at light and may stop unicell algae defense. It may also promote the algae killing bacteria as could some filters.

 

[ctrgojo]

I just got a bottle of the extract for the new pond... not seeing any difference for better or worse. Just awitingin on teh second 55 gal filter to kick in the first has been running a month now...

 

[bsr8129]

Ahhh so no easy way to make green alge go away I think the best bet us uv. My mom has it on her pond that has no plants and way over loaded with fish but has crystal clear water I might just have to break down and get a uv light

 

[Waterbug]

Adding a UV light will not make crystal clear water any clearer.

 

[bsr8129]

I need clear water before I can get crystal clear

 

[DrDave]

An with a good bio filter and plants, you won't have green water.