What is the best way to clean records?


This was a quest I feel I accomplished. The ultrasonic cleaners seemed to be the best way. I bought a VPI Cyclone and returned it without opening the box. I knew that it was very important to well clean records but felt that just vacuuming the wet records was not very effective. That there would be dirt or stamping process solution would remain on the LP. The Kirmiss process seemed very effective but way too complicated, difficult and time consuming. And it still seems like a lot of junk would remain deep in the groves. Then I heard about the rather famous Keith Monks Record Cleaning Machines. Their RCM was developed and used by the BBC. And the machine is used by the Library of Congress and many pros, etc. And I wrote to Better-Records and they told me they use the Keith Monks RCM and most of their better LPs are used and sell for $199++!
I was most attracted by their process of using a medical grade vacuum pump and tone arm like arm with an end piece that runs barely over the record groves slowly removing all the cleaning solution, dirt and the oil-like stuff the use to be able to stamp the records. And it is very gratifying to watch the junk completely removed as the arm  takes about a minute running across to the edge. Every record comes out looking better than a brad new with a surface that shines. And, most of all, the fidelity of the sound has jumped up as much as a major component upgrade. I just emptied my first full jar of dirty solution. Man was it dirty. All that junk was on my records!
mglik
Ijgerens, Benzalkonium chloride is not a surfactant. It is a very strong anti fungal agent. PVC unfortunately likes to grow fungus. The BAK is insurance in this regard particularly with records that you have no idea where they came from of how they were stored. When I lived in Miami I came across several collections that were destroyed by this. If you live in Arizona this may not be an issue.
Benzalkonium chloride is a quaternary ammonium salt which is a cationic surfactant. It is typically used as an antiseptic. It also can be used as an anti fungal agent as you state. It may be fine to use for its anti fungal properties on LPs. My only concern with it is whether it leaves a residue behind after use. Also, BAK would not remove the same contaminants as isopropyl alcohol, so they are not interchangeable.
Yeah, that is a killer SOTA record cleaning machine. Way too spendy for me though! The Walker Enzyme four step Tom recommended works quite well. All the Better-records.com Hot Stampers are cleaned with the Walker process using the RCM. I have quite a few of them, and the ones I have cleaned by hand using Walker and my VPI to vacuum off the final two rinses gets awfully close. The main drawback being its such a big production I tend to wait until there's a stack to make it worth doing.  

He is certainly right about new records needing cleaning maybe even more than used ones. Now that almost all mine are Walker Enzyme'd when a new uncleaned one is played it actually has a greasy sound to it. After cleaning its pristine. The difference is easy to hear, even on a brand new record.