Acidifier v algae?

[micmath]

I noticed that a couple of products that advertise as being algae cures have listed ingredients that seem strange to me. One lists only "salicylic acid", and another lists, more vaguely, "acidifier and buffer". I can find no reference to salicylic acid being effective against algae, and I'm wondering on what basis these products could possibly work (if indeed they do). Is it merely the fact that their products are acidic? I find it hard to believe that any self-respecting algae would be bothered by a bit of acidifier, at least not at levels that would be safe for the rest of the tank.

 

[ian_m]

Looks like it does affect algae.

http://www.ukaps.org/forum/viewtopic.php?f=19&t=19242
and
http://oas.uco.edu/01/papers/lfimple01.htm

 

[micmath]

That's very interesting reading. In particular...

Phosphorus is the limiting nutrient in algae blooms and salicylic acid can block the uptake of phosphorus by algae. Therefore, it is hypothesized that adding salicylic acid to a nutrient rich media like poultry litter runoff water will inhibit the growth of algae.

Thanks for the reference!

 

[plantbrain]

Question is, does it block PO4 uptake in plants also? Or just algae and if so, which species of algae?

 

[micmath]

I wondered about that too. The study that was cited says this about the type of algae affected:

It was also determined that Closterium was the easiest algae to count on the wet mount slides. The smaller spherical Chlorella and Chlamydamonas algae were not seen in the sediment and may have stayed in suspension during the centrifuging process. Plus, it was easy to determine if the Closterium cell was dead or alive due to the color change from green to brown as the cell died. Therefore, it was decided to use Closterium only in the actual experiment and to record the number of dead cells as well as the total number of algae.

So it looks like they only showed an affect on one specific kind of algae, but that was only because they were only looking at Closterium (for practical reasons). I would assume that if a company were to then market a product such as AlgExit based on salicylic acid, they must have access to some more evidence that it works generally the same on all algae, but I have no proof of that. If anyone knows of other studies, I'd love to read them. The label on the product says: "It is harmless for fish, crustaceans and plants," so if you are to believe that then it must not not block PO4 uptake in plants, but again I am only engaging in assumption and welcome anyone who can cite better evidence.

 

[ceg4048]

Hello,
This is an extremely poor assumption. All the algecides that are currently on the shelves of pond shops and LFS also damage plants. It's simply that the plants are have a bit more sophisticated physiology as well as larger food reserves, so it means that they are damaged and not killed outright, however these products incur the same type of damage to plants. After you stop using the products the algae simply returns if the root cause of algae has not been resolved. If the root cause has not been addressed and if the plants are damaged by the toxin, then the algae, who are much quicker to recuperate, attack the weakend plant causing more problems that there was before. This opera is played out all the time because people believe what these companies say. Unfortunately, this is all about marketing and not about truth. For example:

Phosphorus is the limiting nutrient in algae blooms

This is so untrue that it is absurd. Phosphorous happens to be the limiting nutrient for plants, not for algae. Algae do not care about the PO4 levels in your tank, and in fact, when PO4 is limiting, one of the most popular algal species immediately attack, GSA.

One cannot limit or starve algae out of existence without first anihilating the plants. The situation is completely the opposite of what is stated in the quote. If it were true, then adding unlimiting quantities of PO4 should cause algal blooms, right? Well here is a tank which is maintained with Unlimited levels of PO4. Yet algae is zero in this tank. Therefore the statement cannot possibly be true. If you then continue to follow the path of nutrient limitation (which has proven to be a false assumption in the planted tank) and if you continually invoke a policy of toxicity, you are doomed to failure.

Cheers,

 

[tonyg1]

mmm salicylic acid is for all intents and purposes aspirin(derived from the bark of a tree),if it is proven to be a good algae remover i'd just desolve a few in water and bung it in the tank and not bother paying silly money for a proprietary brand.