If you are new to processing film and to Rondinax tanks and their clones, downloading the Instruction Manuals is a first step to learning how they work and how to work them.
However, there are some things to ignore. Look at the instructions for the developer and fixing you are using, not the manuals. Correct the development time for the agitation method (see my post of 30 October 2013) and follow the instructions for fixing that are on the modern fixers.
The reason long fixing times are advised in the 1930s-70s manuals is that the fixing agent was sodium thiosulphate (thisulfate in the USA, and now apparently in the UK as chemists seem keener on standardisation that etymology). The rapid fixing agent, ammonium thiosulphate, was available then (Amfix by May & Baker, for example) but it was not in common use. Now it is just about the only one available since some more modern films will not clear properly with the slow-acting sodium salt. For the Rondinax user this change is very welcome since it means only 2 minutes of turning the knob rather than 10.
The instruction manuals suggest three rinses between developer and fixer. I only use one and have ever used one. The only advantage I can see for more than one is that the acid fixer would be less contaminated by the generally alkaline developer and might, therefore, stand more re-use. I do not re-use my fixer these days since I only process a film occasionally.
Ideas and evidence on washing films after fixation have also changed. You can read more on washing films on my other blog:
I used to remove the reel from the tank and put it in a bowl under the tap. I have now taken to washing films developed in the Rondinax in 8-20 changes of fresh water giving the winding knob a good twirl each time. I do this with the lid off the tank and simply fill the tank to the top (not half-full as with developer and fixer) each time. I have never used anything but tap water at whatever temperature it came out and have never had any sign of reticulation. I add a couple of drops of wetting agent to the final rinse.
In hard water areas, like Cambridgeshire and parts of Bedfordshire where chalk deposits form as water dries, I recommend two final rinses in distilled or deionised water (as used for car batteries).