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Algaecides (not Glutaraldehyde)

I’m thinking out loud here, but would I have two thoughts.
Thought A), running a permanent algaecide seems like a bandage to mask many ills.
Thought 2) would running a permanent algaecide not be detrimental to biofilm formation and a negative for the carbon/sugars/organics cycling and therefor not really very good for overall tank health?
Ideally, you would like to fix the fundamental problems to control algae rather than to rely on algaecide.

There are, however, situations where use of algaecide is unavoidable. I have a planted bowl in my window sill that receives afternoon sunlight. I cannot dial down sunlight, and placing a sun screen behind the bowl will affect visibility and aesthetic. Thread algae (spirogyra, Clado) thrive in intense sunlight and nothing worked until I use AlgaeFix which is commonly used by koi pond owners.

I also have high tech tanks with large cichlid that generate heavy bioload which is magnet for algae. I can't reduce the bioload by giving up keeping cichlid, and my solution is to dose Glut and spot treat with peroxide in weekly water change. Glut is the safest algaecide for livestock and plants, and I don't think I can have algae free planted cichlid tanks without it.

Tom Barr used Glut and peroxide to take care of clients tanks and recommends dosing them for routine tank maintenance practices.
 
API AlgaeFix is a 4.5% solution of Poly(oxyethylene) (dimethylimino) ethylene (dimethylimino) ethylene dichloride, according to this source, and I am linking a safety data sheet for that molecule here because it details aquatic toxicology.

The safety of both peroxide and glutaraldehyde has been discussed many times before on this forum. This thread excludes glutaraldehyde.
This thread is looking at naturally occurring organic compounds, including those that are known to be allelopathic.
API AlgaeFix and APT Fix: thanks for mentioning them anyway.

I'm going to chill out for a while and then come back to this topic to do a bit more reading, but feel free to flood in more ideas for naturally occurring organic molecules in the meantime.
 
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API AlgaeFix is a 4.5% solution of Poly(oxyethylene) (dimethylimino) ethylene (dimethylimino) ethylene dichloride, according to this source, and I am linking a safety data sheet for that molecule here because it details aquatic toxicology.

The safety of both peroxide and glutaraldehyde has been discussed many times before on this forum. This thread excludes glutaraldehyde.
This thread is looking at naturally occurring organic compounds, including those that are known to be allelopathic.
API AlgaeFix and APT Fix: thanks for mentioning them anyway.

I'm going to chill out for a while and then come back to this topic to do a bit more reading, but feel free to flood in more ideas for naturally occurring organic molecules in the meantime.
According to the the link you provided for API AlgaeFix , I summarized the aquatic toxicity data below.

LC50, Fathead Minnow (Pimephales promelas), larva(e), 353.0 UG/L, 48 H, Mortality
LC50, Rainbow Trout (Oncorhynchus mykiss), 44.00 UG/L, 48 H, Mortality
LC50, Harlequinfish (Rasbora heteromorpha), 660.0 UG/L, 24 H, Mortality
LC50, Channel Catfish (Ictalurus punctatus), 3350. UG/L, 48 H, Mortality
LC50, Zebra Mussel (Dreissena polymorpha), 60000. UG/L, 48 H, Mortality
LC50, Water Flea (Ceriodaphnia dubia), neonate, 218.0 UG/L, 48 H, Mortality

According to my calculation, API recommends dosage of 1 ml of 4.5% solution to 38L of water will result in 1.18 ppm or 1180 ug/L concentration. So it is not a safe dosage for most tested animal. Why is there no margin of safety.
 
This thread is looking at naturally occurring organic compounds, including those that are known to be allelopathic.
It appears that Algexit is the only commercial algaecide that contains a natural allelopathic extract, Salicylic acid from Willow bark. But Salicylic acid is now mass produced synthetically to make Aspirin. It will be worthwhile to investigate the dosage and toxicity of aspirin remedy.

More aquarists use real plants for allelopathic algae control. for example, Hornwort has been proven and recommended as companion plant to control algae in ponds and fish tanks.
 
Why is there no margin of safety.
I did wonder about that. I think it is because it does not persist for very long in aquarium water, so fewer people have observed acute toxicological symptoms in their livestock.

@Nick potts @jaypeecee - Hello again Nick and John. I wondered whether you might know the concentration of salicylic acid used in your algae treatments please?
I've got a rough guess of the effective concentration for salicylic acid to inhibit algae, and I can look into the aquatic toxicology later. I just wondered because it would be interesting to see the dosage that they have selected.
 
I did wonder about that. I think it is because it does not persist for very long in aquarium water, so fewer people have observed acute toxicological symptoms in their livestock.

@Nick potts @jaypeecee - Hello again Nick and John. I wondered whether you might know the concentration of salicylic acid used in your algae treatments please?
I've got a rough guess of the effective concentration for salicylic acid to inhibit algae, and I can look into the aquatic toxicology later. I just wondered because it would be interesting to see the dosage that they have selected.

Sorry no idea, I can't find any concentration information on algexit/
 
@Nick potts - Thanks for looking :thumbup:
I may just drop them an email, but I am already suspecting it would be far cheaper to make from scratch, so I'll have to thrash out the desired concentrations later.
It is only £15.99 for 200 grams of 99.9% pure salicylic acid powder on Ebay (with free delivery), and I am guessing that would be enough powder to last a lifetime.
 
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I did wonder about that. I think it is because it does not persist for very long in aquarium water, so fewer people have observed acute toxicological symptoms in their livestock.

@Nick potts @jaypeecee - Hello again Nick and John. I wondered whether you might know the concentration of salicylic acid used in your algae treatments please?
I've got a rough guess of the effective concentration for salicylic acid to inhibit algae, and I can look into the aquatic toxicology later. I just wondered because it would be interesting to see the dosage that they have selected.
API info says that AlgaeFix degrades in 24 hours, enough to kill off some test animal, such as, LC50, Harlequinfish (Rasbora heteromorpha), 660.0 UG/L, 24 H, Mortality. Glut is similarly degradable in 24 hours, but the recommended dosage has huge safety margin of 4 to 10x. AlgaeFix is an O2 scavenger, and live bearers are reported to be specially vulnerable. I only used it in my window sill planted bowl with a paradise fish with no issue, and Paradise is an air breather. I have no courage to use AlgaeFix in my community planted tank while I have total confidence and used Glut for years.

The gardening forum recommends dosing one aspirin per liter for plants, but the info is incomplete without toxicity data.
 
Hello again Nick and John. I wondered whether you might know the concentration of salicylic acid used in your algae treatments please?
I've got a rough guess of the effective concentration for salicylic acid to inhibit algae, and I can look into the aquatic toxicology later. I just wondered because it would be interesting to see the dosage that they have selected.
Hi @Simon Cole

The recommended dosage for Blue Exit is 10 ml per 80 litres daily over the course of 5 consecutive days. As a preventative, dosage is 10 ml per 80 litres weekly. The instructions for use also make a point of saying "Does not contain erythromycin". In practice, the dosage can be significantly increased. I had a dialogue with Easy-Life some time ago and they sent me a report carried out by an independent body. I'll see if I can find it.

JPC
 
The gardening forum recommends dosing one aspirin per liter for plants, but the info is incomplete without toxicity data.
Interesting thread.

One paper suggests acute LC 50 for juvenile zebrafish is 567 mg/l .
Another paper suggests levels of 40 mg/l had no detrimental affect on growth rates in the same fish.

Interestingly the paper concerning acute toxicity makes mention of algal toxicity (EC50) to salicylic acid to be greater than 100mg/l?


 

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Hi @Simon Cole

The recommended dosage for Blue Exit is 10 ml per 80 litres daily over the course of 5 consecutive days. As a preventative, dosage is 10 ml per 80 litres weekly. The instructions for use also make a point of saying "Does not contain erythromycin". In practice, the dosage can be significantly increased. I had a dialogue with Easy-Life some time ago and they sent me a report carried out by an independent body. I'll see if I can find it.

JPC
What is the effective concentration of salicylic acid, that is, ppm or mg/L, in the recommended dosage.
 
Interesting thread.

One paper suggests acute LC 50 for juvenile zebrafish is 567 mg/l .
Another paper suggests levels of 40 mg/l had no detrimental affect on growth rates in the same fish.

Interestingly the paper concerning acute toxicity makes mention of algal toxicity (EC50) to salicylic acid to be greater than 100mg/l?


So if I dissolve one 350mg aspirin in a L of water, it will have enough strength to inhibit algae without killing fish, assuming that aspirin and salicylic acid are gram equivalent. That is a cheap source of algaecide. I may test it out in my planted bowl.
 
So if I dissolve one 350mg aspirin in a L of water, it will have enough strength to inhibit algae without killing fish, assuming that aspirin and salicylic acid are gram equivalent. That is a cheap source of algaecide. I may test it out in my planted bowl.
Well if my understanding of the above papers are correct (there's no guarantee that's the case) then yes you'd be correct, however the lc50 number mentioned above killed 50% of zebrafish in 48hrs, also worth mentioning the lc50 for zebrafish embryos was only 274mg/l in one paper and Lowest Observed Effect Concentration =37mg/l in another, so I wouldn't be dosing 350mg in a litre of water that contained livestock.

Again my interpretation of above papers could well be flawed.

Edited for clarity.
 
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Hi Folks,

Are we not in danger of equating aspirin wth salicylic acid? According to Wikipedia, "Salicylic acid has long been a key starting material for making acetylsalicylic acid (aspirin)". I think we need to proceed with caution. If not, I fear there's a risk of livestock casualties. And I, for one, want no part in that.

JPC
 
The gardening forum recommends dosing one aspirin per liter for plants, but the info is incomplete without toxicity data.
Hi @tiger15

Information from a gardening forum is of limited use. Not only did they not have to consider fish toxicity but they may not have had a need to consider bacterial toxicity. Or water oxygen level, etc.

JPC
 
Hi Folks,

Are we not in danger of equating aspirin wth salicylic acid? According to Wikipedia, "Salicylic acid has long been a key starting material for making acetylsalicylic acid (aspirin)". I think we need to proceed with caution. If not, I fear there's a risk of livestock casualties. And I, for one, want no part in that.

JPC
True, aspirin is not the same as salicylic acid, even though it is a precurser to make aspirin. There are no aquatic toxicity data for aspirin, but data are available for salicylic acid from Easy Life and other sources as posted in 52 and 55. I wouldn’t use aspirin with life stock, but plant only set up is a possibility. It is not necessary to substitute aspirin for salicylic acid as salicylic acid is readily available OTC for topical treatment of skin ailments.
Hi @tiger15

Information from a gardening forum is of limited use. Not only did they not have to consider fish toxicity but they may not have had a need to consider bacterial toxicity. Or water oxygen level, etc.

JPC
Garden forum info cannot be trusted , and this is why I said the info is incomplete. Florists have used aspirin to treat plants for ages and there may be some merit to it in suppressing algae and bio fouling. You will not find aquatic toxicity data on aspirin unless you generate your own as it is not an ingredient of any commercial biocide.
 
You will not find aquatic toxicity data on aspirin unless you generate your own
There is some data out there for Acetylsalicylic Acid, the fish used were Carp, over a 12 and 21 day period they were administerd 100mg/l and 200mg/l of ASA.
I don't have full access to the paper so haven't read their test procedures, but have requested it and will post here if I get it.

Take home from the article was..

"From the results, it is noteworthy that the drug ASA even at considerable environmental concentrations causes negative impacts on the health of aquatic organisms. The alterations of these parameters can be effectively used to monitor the impact of pharmaceutical drugs in the aquatic environment."

 
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There is some data out there for Acetylsalicylic Acid, the fish used were Carp, over a 12 and 21 day period they were administerd 100mg/l and 200mg/l of ASA.
I don't have full access to the paper so haven't read their test procedures, but have requested it and will post here if I get it.

Take home from the article was..

"From the results, it is noteworthy that the drug ASA even at considerable environmental concentrations causes negative impacts on the health of aquatic organisms. The alterations of these parameters can be effectively used to monitor the impact of pharmaceutical drugs in the aquatic environment."

Interesting finding. My interpretation of this study is that carp can survive 12 to 21 days at 100 to 200 ppm ASA notwithstanding some negative blood effect. This means it is safe to dose one baby aspirin or 89 gm daily to carp, and probably also OK to dose full strength or 350 gm non daily. The question is whether there is sufficient strength to inhibit algae and what kind that only aquarists can find out themselves by experimentation.

Aspirin is a magical drug that can do so many things that scientists still do not understand fully how it works. I have been taking baby aspirin daily for years as recommended for and now against by scientists and will cost me nothing to test it out with my plants.
 
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