Copper

[reynolds357]

I have a question about a particular use of copper as an algae killer. I know the staining issues with copper and am aware that many do not like it for this reason. I use copper in a slightly different manner and have had wonderful success with it. On yearly opening, and on the rare occasion I have water problems due to low Chlorine(vacation or business trips away from home), copper has been an easy answer that has not stained anything. I bought a large supply of 99.8% elemental copper that is commercially designed to kill algae in ponds. I paid $21 for it a long time ago. There is more copper in that bucket than $2000 worth of commercial pool algecide would have in it. The beauty of this stuff is that it will clear up a light bloom or a swamp in 48 hours and it will do it without using much chlorine. Where I favor it over the chelated coppers is that once it has done its job, I can get it out of the water very easily. I put enough of it in the watter to turn the water an opaque cloud. I filter for 48 to 72 hours. I usually have to back wash three or four times during that process. Each backwash is loaded with blue colored dead algae. During the two to three days I do this, the water clears up some but, it still remains visibly cloudy. When the algae is dead, I add Zeo Fiber to my sand filter. I let the filter run until the pressure reaches 20psi. It usually takes a day and a half to two days for this to happen. By this time, the water is sparkling clear. I backwash out a huge mess of blue zeo fiber containing dead algae. After backwashing the Ze0-Fiber, the copper is gone from my water. I add Zeo fiber back to the sand filter and usually its ready for a backwash in about a week. After that back wash, the copper will test at zero. I am sure its not truly zero, but its definitely not high. Nothing has ever gotten stained during the process. I am using $1 worth of copper and $2 worth of Zeo Fiber to do what I would use $30 worth of chlorine to do. So far, I have never observed a negative side effect from this process. I keep the pool swimmable during the entire process. I doubt anyone with blonde hair would want to get in, but its not going to stain my Cherokee Indian hair.

Is anything wrong with this?
Is there something I am over looking?

 

[Patrick_B]

Each to his own, but I greatly prefer bleach in keeping and algae outbreak at bay with steady control of FC. However things happen with all of us and with an algae bloom of any kind, I would have a strong perference for killing it with bleach. No metal addition for me as I don't want to risk it at all. I do seriously doubt you have a zero dissolved copper residual even after the filtering you mention.

 

[duraleigh]

As brushpup says, to each his own. TFP would NEVER suggest that as an acceptable method. Dissolved copper does not filter from pool water and having zeo instead of sand does not facilitate it's removal.

Glad your method is working for you but no one reading this should take away that copper is in any way a suitable method for long term algae prevention. You need the chlorine as a sanitizer anyway so use it as an algae preventer as well.

 

[JasonLion]

You have been very lucky.

 

[reynolds357]

The difference in this form of copper is that it is never truly dissolving. It is suspending. A small amount might truly dissolve, but it lacks the added ingredients that the commercial pool algecides have to make it fully dissolve. I used a commercial copper algecide the first year I had my pool. It turned everything black that was within an inch above the water line. This form of copper does not seem to have this side effect when left in this amount of time. I discovered it because as part of my job I maintain pumps that circulate settling pits for water that is used in a commercial stone sawing facility. The algae will grow on the pump intakes and restrict the flow. This form of copper will kill the algae in the settling pits with absolutely no chlorine present. I figured I would give it a try in the pool, and it was equally effective there. I would bet that if I ever used it in the presence of a chelating agent that I would run a significant risk of staining everything black. In this suspended form, it seems to work very well.

 

[duraleigh]

What do you use for a sanitizer?

 

[chem geek]

Have you tried this in a plaster or fiberglass pool or only in a vinyl pool?

 

[reynolds357]

Only in vinyl pool. I use Sodium Hypochlorite and Calcium Hypochlorite. MY CA is lower than my test kit is capable of testing for.

 

[chem geek]

Well that may explain why you don't see problems. If you were to try your approach in a plaster or fiberglass pool you might see staining on pool surfaces.

By "CA" do you mean Cyanuric Acid (CYA) or Calcium Hardness (CH)? I presume probably CYA. Why is the CYA so low in the pool? Is it not outdoors exposed to sunlight or are you talking about opening a pool and the CYA has gone?

Also, do you lower the pH prior to treatment or do you know the pH when you typically treat with copper?

Even though you remove a lot of excess copper that has precipitated, you'd still have some leftover that could stain if the pH rose. If towards the end of your approach were to raise the pH, then you could form more precipitate to filter out and after removing that from the filter you could then lower the pH and have less risk of future staining. The problem is that in a plaster pool it might be hard to not get staining during this process. Plaster surfaces tend to be of higher pH which is one reason they promote staining. Also, their chemical structure has metal oxides-hydroxides bond to them more than to vinyl.

 

[reynolds357]

I meant Cyanuric acid by CA. I keep it low intentionally. I have much less water trouble now that I had years ago when I kept it normal to high. I kind of stumbled up on not using CYA by accident. It never was really high at any time. The highest its ever been was 60. I started using Sodium Hypochlorite and Calcium Hypochlorite for sanitizing and shock. Through back wash, vac to waste, waste from rain, lowering pool level for closing, etc. the level just worked its way down. To make a long story short, I use much less chlorine for shocking and a bit more for sanitizing. Economically, it seems to be about the same cost stabilized or unstabilized. The thing I really like about it being unstabilized is I rarely ever have any combined chlorine. Pretty much a combined chlorine test will always be 0. I have had to shock one time this season due to C.C. The other times I just shock to be proactive and make sure I am ahead of any algae or chlorine resistant microbes. I use about $1 per day for chlorine for sanitizing and probably $4 worth about once every 10 to 16 days for shocking.
My PH is 7.1 to 7.3. PH is rock solid and does not usually move unless I try to move it.

 

[costablanca blue]

i´m with reynolds on this - bbb sounds great but a little copper helps massively in controlling algae.

the only real down side of copper (in what ever form) is slight staining of the pool surface. most pools where i work are gunite and mosaic tiles and the copper only stains the grout slightly. i´ve never seen it stain the mosaic tiles. grout discolouration is only noticable to pool owners after many years of use. by that time the pool needs to be regrouted anyway and you´ve got a blank (white)canvass again.

water isn´t cheap here and pool owners aren´t interested in diluting to control cya. liquid chlorine is impossible to carry around all day in 110F. swcgs are too expensive. i´d be stuck without a little of the blue stuff!

ps sorry, i guess í should say color, not colour. i love visiting the usa but don´t see why you have to change the spelling. :-D

 

[chem geek]

Pool services that only visit once a week have fewer options so controlling algae when chlorine levels may get low or the CYA high by using some form of algaecide makes more sense, though the side effects of whatever is used are the tradeoff.

As for CC, mine is always <= 0.2 ppm and I have 40 ppm CYA with the FC between 3-5 ppm usually. Most on this forum have very low CC as well. So it's not necessary to have the CYA below the measurable limit. It is true that you don't want the FC/CYA ratio to get too low, but a low CYA will have greater loss of chlorine from sunlight so for an outdoor pool that doesn't work as well, especially if the chlorine is manually dosed.

 

[duraleigh]

emphasizing chem geek's post. Practices for pool services are just that and not the best path for residential pool owners managing their own pools.

TFP does not suggest the use of copper in any form in any pool....the side effects are too costly and the need for it is simply non-existent in a well managed pool.

 

[Patrick_B]

i´m with reynolds on this - bbb sounds great but a little copper helps massively in controlling algae.

the only real down side of copper (in what ever form) is slight staining of the pool surface. most pools where i work are gunite and mosaic tiles and the copper only stains the grout slightly. i´ve never seen it stain the mosaic tiles. grout discolouration is only noticable to pool owners after many years of use. by that time the pool needs to be regrouted anyway and you´ve got a blank (white)canvass again.

water isn´t cheap here and pool owners aren´t interested in diluting to control cya. liquid chlorine is impossible to carry around all day in 110F. swcgs are too expensive. i´d be stuck without a little of the blue stuff!

ps sorry, i guess í should say color, not colour. i love visiting the usa but don´t see why you have to change the spelling. :-D

Our philosophy is not diluting to control CYA, but to keep it from rising to that point in the first place. Pool stores and others could care less about this, don't realize it's importance, or don't know anything about it all.

Personally my philosophy is that putting ANY metal in the pool for any reason is a very, very, bad Idea. The risk of staining and ruining the look of a pool finish is far too great. Chlorine is CHEAP, and there isn't anything better in my opinion.

 

[reynolds357]

My pool philosophy is pretty similar. My CYA is below 20 at the moment. I think I will raise it back up to about 30. To do it, I am going to use some handy tri-chlor pucks. I guess my approach is similar to the BBB method. My method is BBB 95% of the time with the addition of Cu. I love Copper. Its really nice to know that if I want to leave the house for 10 days that I can shut the pool down and when I return there is going to be no algae if I dose before I leave. If I don't, then its nice to know I can have it dead and gone in three days.

 

[duraleigh]

Seems like we are starting to beat a dead horse just a bit. This has been a very good discussion with logical, polite dialogue.

Experience indicates that as these topics continue, they can deteriorate into harsher language.

I'll leave it open a bit longer in case anyone wants to add something but then it seems time to lock the thread.

 

[chem geek]

The way I look at it, there is a difference between a basic system with a simplifying philosophy that is the recommended approach vs. being more advanced and knowing the pros and cons of other alternatives and making an informed decision. When we say we would never recommend something, at least for me I would say that is in terms of keeping things simple and safe and fairly generally applicable. I would not tell anyone never to use copper, but would always tell them about the risks. That is different then telling someone never to mix Cal-Hypo with Trichlor which is truly dangerous (explosive fire hazard with noxious fumes).

If you want to prevent algae growth in case the chlorine level gets too low, such as leaving on vacation and not having the pool maintained, there are several ways you can do that, not just using copper ions. You could add a large dose of Polyquat 60 which will at a minimum inhibit the algae to a very slow growth rate and you could just do that when needed, not all the time (unless you wanted insurance). You could use a phosphate remover which would slow down the algae growth even more assuming there aren't organic phosphates in the water (say from dead algae).

Ever since I had the phosphate remover experiment done as I describe in the thread Orenda Technologies PR-10000 and CV-700 Products, my pool has been far less "reactive" and I can easily skip a dose of chlorine and the pool remains clear. I know that there is virtually no algae growth in the pool because the chlorine does not get depleted to zero if I accidentally skip dosing whereas before when phosphates were high if the FC/CYA got too low then algae growth got the chlorine to zero within a day or two and had the water turn dull to lightly cloudy in a day or two after that, but I could shock the pool to get it clear within a day or two as well. In an extreme case upon one opening (starting of the solar system), when the chlorine got to zero and bacteria could grow, I had bacterial conversion of CYA into ammonia as I describe in the thread It Can Happen to Anyone - Zero Chlorine, CYA --> Ammonia.

So would I use a phosphate remover again? Probably not. It was a free experiment from which I received the benefit of extra insurance from algae, but even if I did let the chlorine get low and algae were to grow I could shock it and get the pool back to normal in a few days, not a week. You may think you only get this benefit from copper, but that is not the case. You could get similar results with Polyquat 60 or from a phosphate remover, neither of which have any risk of staining and where Polyquat 60 is the most economical because you only need to use it when you want to (phosphate removers can be expensive if phosphate levels are high).

 

[reynolds357]

Duraleigh, you will never get harsh language from me. I appreciate your forum. It contains a wealth of knowledge that benefits me greatly in my pool care. I am not here to disrespect you in any way. I am only here to learn. I am here as your guest. I started this thread in essence to find out if staining was the only negative effect of Cu. I love the use of Cu. I am in no way trying to push it on anyone. I was simply seeking information as to whether there is any consequence other than staining associated with the use of Copper.
Something stated in these answers then made me wonder about tri-chlor. When the level of CYA needs to be raised, what is wrong with using tri-chlor to do this? As a side effect of using tri-chlor, you get to have a few weeks of loading the chlorine feeder and getting a break from Sodium Hypochlorite pouring every night. The acidity of the tri-chlor also gives the opportunity to raise the borate level a bit without having to pour acid.
I do use Polyquat. To me, it seems to be a very effective preventative. It also seems to be pretty poor at getting rid of the algae.

What bacteria would be required to start CYA to Ammonia conversion? That has me curious. In the off season, that might be a strategy to eliminate CYA in pools. Ammonia is pretty easy to get rid of.

 

[JasonLion]

Trichlor has it's uses. The main issue is that it adds CYA too slowly for most people who want to raise CYA, and too quickly for people who use trichlor all the time. The fairly rapid rate at which trichlor lowers PH also causes problems for a lot of people.

As long as your know what all the "side effects" of using a particular chemical and take them into account there are cases for copper and trichlor use. But those cases are not common, and even people who think they know what they are doing tend to make occasional mistakes with both of them. With copper the worst case problems are far worse than with just about any other common pool chemical, so even though those problems don't happen to everyone, it hardly seems worth taking the risk.

 

[chem geek]

So as you have learned, in addition to the risk of metal staining from too high a copper level or pH combination, one can also have blond hair take on a greenish tint from copper in the water. There is also the environmental risk of dumping pool water with copper since it will kill not only algae, but is harmful to aquatic wildlife (see this report) and it does not degrade in the environment so the pollution is persistent. Of course, one presumes the pool water you dump will get vastly diluted, but if it doesn't or if it accumulates, it can kill fish and other aquatic wildlife. Chlorine is also toxic, but far more easily removed as any reducing agent will dechlorinate the water. Borates are also persistent, but are less toxic than copper especially as they are diluted (see this link).

[I wrote this as Jason was responding] As for using Trichlor to raise the CYA level, it is slow to do since Trichlor dissolves slowly, but if that is not a problem then the only other side effect to using Trichlor is that it is acidic so requires a base to adjust the pH such as using 20 Mule Team Borax or washing soda / soda ash or even caustic soda / lye. So what you wrote is correct. If you need CYA higher in a hurry, then it's not a good approach, but if you've got time then it's fine and if you use Borax to compensate for the pH then you increase borates as well, assuming that's what one wants to do. Many people on the forum do use Trichlor on occasion and that's another way to deal with chlorine dosing during a vacation (up to a week, not much longer).