Dear Sue:

Pete Giwojna

Dear Sue:


I have not heard of any adverse effects from using Rowaphos to control phosphate levels in a marine aquarium, Sue, but I have never had occasion to use it in a seahorse tank, so I cannot say from my personal experience whether or not it could be harmful at all to the gills of the seahorse.


The active ingredient in Rowaphos and most other phosphate absorbers is ferric hydroxide, so it does contain an iron-containing compound, and if you have any concerns whatsoever that the Rowaphos could irritate the gills of the seahorse, then I would recommend using a phosphate remover that does not rely on the ferric hydroxide.


In your case, I believe that Phos-Zorb by Aquarium Pharmaceuticals would be an excellent choice for this purpose because it consists solely of activated alumina, rather than ferric hydroxide, so it does not contain any iron that could have any harmful effects on the seahorses. The Phos-Zorb is especially helpful for eliminating problems with brown nuisance algae due to diatoms because it removes silicates as well as phosphate, and diatoms require silica in order to grow.


Here is some additional information about the Phos-Zorb, Sue:


<open quote>

Aquarium Pharmaceuticals Phos-Zorb




Filstar Phos-Zorb is a special filtration material, packaged for use in all API Rena Filstar XP Series Canister Filters, but can be used in other applications. Phos-Zorb selectively removes phosphate and silicate. Phosphate is a by-product of fish metabolism, decaying organic matter, and is an additive in some water conditioners and filter medias. In saltwater aquariums, excess phosphate lowers the available calcium and magnesium necessary for the growth of hard corals and other invertebrates. Excess phosphates also promotes the growth of unwanted nuisance algae, and can lead to poor coral health and bleaching. Silicates promote the growth of unwanted brown diatom films.


Ingredient: activated alumina, 100%




Rinse pouch under tap water for several minutes to remove dust and to activate. The activation process will temporarily generate some heat. Replace pouch every 2 months or when testing indicates presence of phosphate or silicate.

<close quote>


In short, avoid using the Rowaphos (or any other phosphate remover containing ferric hydroxide), Sue, and try the API Phos-Zorb instead.


If you cannot find it in any of your local fish stores, you can obtain Phos-Zorb online from Drs. Foster and Smith. Just copy the following URL, paste it in your web browser, and press the “Enter” key, and it will take you directly to the right webpage to order the Phos-Zorb:


Good luck!



Pete Giwojna, Ocean Rider Tech Support





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