philip wrote: "This site doent have much activity. Floaters seem to just get the tank and keep it to themselves."
There are probably a few things that contribute to a general lack of activity here. Firstly, if I had to wager a guess at the number of peple who ever hear of (and susequently look into) floating I'd say
much less than one percent of the general population know and/or care much about floating. Of that fraction of a percent there are probably relatively few who decide to buy and/or maintain their own tank, then of those many who don't use or have access to the internet, and then of those there are only so many who bother to search for a forum which discusses float tank construction and eventually arrive at this website whose domain name really gives no indication that it has anything to do with floating (no offense intended to the owner).
That would indeed leave very few people to eventually come across this website/forum. And of those few, they have to go through a vetting process with the owner of the website/forum who, even after it is determined that you are not a bot and allows your account to write posts, still retains the "approve each post" functionality, which really IMHO puts people off of the whole thing because it can take a few days (or longer) to get one's post to display and then you may not ever get an answer. And with forums, this sort of discouragement can prevent a forum from gathering the 'population' needed to be useful and active. Sad but true.
Perhaps if people get impatient in wanting float-tank questions answered they will not bother to ask their questions here and will just purchase the instructions (which I believe this website's owner sells).....things that make ya go 'hmmmm'.......

. The thing to keep in mind is that this forum seems to be built/maintained as a voluntary service, making this a free resource, and so one proverbially gets (little more) than what one pays for.
Aside from all that, the John Lilly book seems to be a great resource, and until such time as this forum were to become active and bustling with useful discussion, it may remain the best source of information (outside of the plans one can purchase for a nominal fee).