There is information on this filter out there. There are considerations involved that the marketing material doesn't want to discus. Their materials try to hide all the downsides. And their is contradictory information in their literature.
Next, this is not a brand new product by any means. You can read a review of it in the December 5, 2012 edition of Practical fish keeping here
http
/www.practicalfishkeeping.co.uk/content.php?sid=5376 However, more interesting is a thread on their forum which was a follow-up on the article and is a good read
http/forum.practicalfishkeeping.co.uk/showthread.php?t=117475
So, as I am inclined to do, I began to research the processes involved and based on my reading, I would actually advise one not to use this product. But the most interesting part of how it works can really lead to a major disaster during a power failure.
Hydroxal radicals will only have an effect on NH3 but not on NH4. This is important in terms of cycling related issues. The Ammonia oxidizing organisims in our tanks consume NH3 not NH4. In most water when NH3 is created by fish and organic decomposition, most of it almost instantly become NH4. This equilibrium will be maintained until both forms of ammonia are removed. The higher the pH of the water, the greater the portion of the total ammonia that will be in the form of NH3.
If you believe what has been written about the filter, you find that it tends to remove ammonia from a tank pretty fast. So. there will be very little NH3 available for very little time. This is one of the biggest selling points for this filter. But there is another aspect to this. If the NH3 is removed from the water rapdly, it is not available to feed the ammonia oxidizing bacteria. The result is there is little or no nitrogen cycle established in a tank. When there is a power outage, the toxic NH3 will stop being converted to NH4 by this filter and it will build up because the tank has very few of the bacteria needed to handle it. if it works as advertised, the Hydra filter has assured that will be the case. We all know how fasttoxic ammonia can build up in fully stocked uncycled tank. How long of a power cut can any tank relying on this filter withstand?
I have had electrical outages that lasted for many hours, even a day, and as long as I aggitated the water surface using battery powered air pumps, all went just fine. You do not need a constant application of an air stone to do this, Using two units rotated between 15 tanks worked fine for me. I moved the pumps from tank to tank.
But perhaps some of the better threads I have seen on this filter can be found here
http/www.ukaps.org/forum/threads/ocean-free-hydra-electro-plate-filtration-thoughts-please.35913/ And the best one of all is here
http/www.cichlid-forum.com/phpBB/viewtopic.php?f=6&t=242062 The most amusing thing in this link was the posting of a sw tank pic after it had been made clear the forum is for fw only, so sw info is not relevant. The poster stated the sw reef tank in the pic got no water changes for 6 months, only topped up for evaporation. How often does the normal reef change w/o this unit get water changed? I can find lots of threads where people say do them once a month or every two months, but I also find many who say they are doing no changes for between 6 months to several years. Here is an example of this sw dichotomy
http/www.thereeftank.com/forums/f190/riddle-me-this-batman-no-water-changes-for-3-years-80768.html
However, since Alasse seems willing to give this filter a try, I assume she has done bit of research herself into the processes involved and the potentials for both good and bad things that they might cause. I assume she has considered the costs involved too. So I, and I assume other readers of this thread, would be very grateful if she could better explain the science behind the product since the literature from the maker is light on this aspect and somewhat confusing. I would be happy for her to explain why some of the objections raised in the links I provided and the opinions I have stated in this thread are of no concern. Please, Al, can you show us why you think this product is worth "looking at" rather than merely saying you do not care what I think about it which gives no help to anybody in understanding the product and why is should be considered. If you need to get a bit scientific, we can start a thread in the scientific section if you prefer?
One last thought here. The Hydra filter is not all that new. It has been around for several years. If this was an amazing product which did all it boasts, why is it not being rapidly adopted all over the place in all sorts of tanks. There are many, many, many millions of tanks all over the world. There have to be 100s of millions of filters from simple air powered sponges to sophisticated sw systems and everything between running on them. As far as I can tell there are only a few 100,000s of these filter that have been sold worldwide in that time?
In the United States, as of 1996, aquarium keeping is the second-most popular hobby after
stamp collecting.
[28] In 1999, an estimated 9.6 million US households owned an aquarium. Figures from the 2005/2006 APPMA National Pet Owners Survey report that Americans own approximately 139 million freshwater fish and 9.6 million saltwater fish.
[29][30] Estimates of the numbers of fish kept in aquaria in Germany suggest at least 36 million.
[28] The hobby has the strongest following in Europe, Asia, and North America. In the United States, 40% of aquarists maintain two or more tanks.
from
https/en.wikipedia.org/wiki/Aquarium
