The betta spledens section is in-tact and has been re-organized to, hopefully, be easier to learn from.
In place of the general aquaria data there are links to other places that have much more in-depth (and less rambly!) guides. I do sincerely hope that this new format will be a lot easier for you to find what you need. It is unfortunate having to remove all that content however a back up has been made so if I can, at a later date, I will have a go at reinstating it.
Hopefully this'll be for the better though. Lord bless you.