Cannot get rid of cyano!

[pseudonym]

Hey Denny!

Thanks for the Zoas BTW.. LOVE them. =) Bring moar!! Are you coming to frag fest?

As for "long term".. running continuously for 10+ years on a system where we have actual research into the effects of skimming as compared to natural ocean reefs, with a control system and then repeating it several times in order to compare. I would say somewhere in the region of 50 - 75 years when added together and run concurrently over that 10 year period. IE: a rigorous scientific long term study of the effects of skimming. Something we don't have and it appears no one is currently doing. That *I* can find at any rate.

Advanced Aquarist published two detailed studies on skimmers. The first was to create a framework for evaluation, the second to actually do the evaluation. The results were surprising to say the least. Looking at the composition of skimmate is suggestive of a vast amount of micro fauna being removed along with organic compounds. Again, the research is very preliminary, we know next to nothing about the effects and while I can look at the composition to say "This is suggestive of" we don't actually KNOW what skimmers remove.

Bacterial counts are very interesting and a huge black hole in our knowledge. it is believed that it may be linked to coral spawning, or it may be linked to general health. We simply don't know. All we can do is compare it to natural systems and say that the count of hydrophobic bacteria is higher than in natural systems. We can't even say what kind of bacteria it is and can only describe general characteristics such a hydrophobic let alone say with any certainty what the long term effects are.

[pseudonym]

Just re-read the study on bacterial populations and protein skimmers. It is even worse than I stated. We can't even say with any certainty that hydrophobic bacteria levels are increased. The exact conclusion is that there is an evolutionary preasure that will almost certainly result in increased populations of hydrophobic bacteria. In the words of the study:

"Aquaria subjected to active filtration via skimming present water column bacteria populations that are approximately 1/10 of those observed on natural reefs. The consequences of this disparity on the long-term health of the tank's livestock are not known. How do reef tank organisms adapt to such a bacteria-deficient environment? Is the whole food web in an aquarium perturbed, or are there compensatory mechanisms that maintain an appropriate energy transduction through all of the trophic levels? Is "old tank syndrome" related to possible nutritional deficiencies stemming from this bacteria "gap"? Alternatively, could "old tank syndrome" be symptomatic of a gradual decrease of bacterial diversity as a consequence of selective skimmer-based removal of only bubble-susceptible bacteria? At present, it is not possible to go beyond speculation on these points - further research is needed."