Ah, see the problem here is that the burden of proof does not lie with my assertion. The burden of proof lies with those who present the statement that I am questioning. That's a simple truth of logic in argument. I am not the one who presents anything as a fact - I said that the fishkeeping world has a lot of bs that is presented as fact, not that I am presenting my hypothesis that corys do fine on their own as a fact. So it is not up to me to show any proof. It's up to the fact makers.
A matter of the scientific method:
One party presents a conclusion - and thus must show solid, irrefutable data to indicate that position as being a fact rather than a hypothesis.
In this case that corys need to be in groups of four or more.
Another party demands proof of that conclusion's basis in fact. Thus solid data, not presentation of credentials or the simple "because everyone who knows their stuff agrees," sort of thing. It has to be solid, irrefutable evidence if there is meant to be an entitlement of fact. This means that any burden of proof lies squarely on the first party.
In other words, I don't have to tell you why it's not - you have to tell me why it is.
The post that nh5 was responding to, posted by Lupin, contained the following:
"(corys)...should be kept no less than four."
Now while I am not solidly disagreeing with Lupin, who is a very knowledgeable and helpful forum member, I am questioning the basic knowledge base that the statement is based upon.
How has this numbered been arrived and agreed upon? For this sort of a statement to hold its role as a "fact" there needs to be empirical data that shows these animals' health and overall well being is and can be documented as affected, and noticeably afflicted when kept in groups smaller than four.
Are there lengths of controlled experimental data where corys were kept in varying numbers, and observed as showing any decline in health, longevity, etc when the number four is breeched? Is there anything to show they live a better life, and perhaps a longer life when kept in groups of at least four or greater? Has anyone recorded such data in a proper scientific manner? Or is it merely as you said - "Every major publication I've read has stated 4+ and most recommend 6+. Every major Cory breeder / expert seems to agree." That isn't empirical, scientific data. That is nothing more than the use of supposed credentials to further the basis of an opinion. Good old "expert opinion." While good, it still isn't irrefutable.
Not that I wouldn't lend a lot of faith to what more experienced and knowledgeable people than myself have to say about certain subjects - but without a solid scientific, provable model to show this as absolute fact, it still holds merely as a theory - and many theories get proven untrue in time. Be honest - didn't the medical community once prescribe bleeding as a form of treatment? Think of how many times back in the day that someone might have said, "Um I think bleeding might not be such a great idea," and it was followed by people saying, "Oh are you arguing with doctors and people who know about this stuff more than you do? I would trust their expert opinion rather than your layperson's point of view." Look who was proven wrong in the end.
And such experiments that are needed to prove this "corys need groups" hypothesis would actually contain far too any variables such as the fact that fish are very strange animals and can often die very suddenly with no signs of disease and in perfect conditions, any slight variances in water chemistry, etc. So even if such an experiment were to have been carried out, there is simply not enough control to merit a solid workable conclusion.
So my rant here is that while in theory it does seem (just like you noticed the difference in behavior when you expanded your cory army) that corys need groups in order to prosper, that doesn't mean it's true by any scientific fact unless someone presents the data, and the data cannot be refuted. Just seeing a change in behavior does not constitute any real proof that the corys are healthier or happier - only that they are exhibiting a change in behavior due to a differing social dynamic. This is not evidence of any increased happiness or increased health. Nor is it evidence that the corys have a preference one way or another.
The burden of proof lies with those who present conclusions, not with those wordy, snide dorks like me who accuse them of spreading a bunch of bs without factual basis.
Depending on the fish you get, fish from slow-moving areas and those with generally long trailing fins will, of course, not appreciate the currents if strong. Only fish with streamline body shape or bodies designed to withstand the currents will do. Your betta certainly will not like it but there are a few exceptions applied. Most people claim their bettas like the currents but the norm is they wouldn't especially with very long trailing fins.
