Audio Desk Ultrasonic Record Cleaner Onwers?

@seasoned 
It doesn't make sense to me, at all.

We all know that the AD cleaner and the Spin Clean use fluid over & over that our records are exposed to in their respective cleaning methods. The Spin Clean fluid has an additive that (supposedly) makes the "crud" fall to the bottom.

The AD cleaner...It's great to clean the filter and change the fluid, but there is another problem... the crap that forms on the inside of the cabinet that can never be cleaned away completely.

Another reason for the DIY method.

I use an Audio Desk machine and love it for the simplicity. I suppose I change the water every 70 LPs or so, mainly because I go slow these days and by that time it feels about right to make a change. A few points: 

I agree that the machine appears to leave a residue and that you can get better sound by rinsing the LP afterward with pure water and a vacuum, or by using a VPI machine instead, for instance, with good fluid like the Audio Intelligent stuff I use. I don't like to admit it, but I do hear an improvement with the AI fluid over the Ultrasonic. But again, it's the simplicity that counts for me - if I had to do every LP on a vacuum machine I would never get around to cleaning my LPs. And having invested money in some decent carts... 

You can clean off the brown crud that accumulates on the brushes after extended use. I do it by removing the two rollers and rubbing them together while dunking them in distilled water. Each one cleans the other. They look great after this.  Might save you a round or two of purchasing new cleaning brushes. 

on the frequency of use: According to the rep in PA you should clean records every three weeks at least, if you keep the machine filled with fluid. Otherwise the water can degrade the water pump, a problem that's prevalent with the earlier, original model machines. I learned that the hard way when my old one had the dreaded water pump breakdown. 

@slaw
My Spin Clean rinse step does not use fluid or brush insert; just deionized water with a few drops of isopropyl.That is followed by a final rinse on the RCM using Reagent Grade water and vacuum.
I have had my AD cleaner now for a couple years and have cleaned hundreds of records. I do not have crud on the outside of the machine; still looks new.

I encourage ADS (or KLA) users to spend $15 on a TDS (total dissolved solids) meter and check the machine’s solution before and after each cleaning session. The solution on the record when the fan starts will evaporate, but whatever solids are in the water will dry on the record.

Don’t change solution based on a certain number of records - change it based on how dirty it is.

The solution gets dirty in a surprisingly short amount of time. The unit’s passive filter helps but only marginally so. Plus, the tank itself retains gunk (solids) record after record after record. All of the single slot desktop machines need active filtration with a fine-grained filter.

The ADS and KLA are okay - anything that encourages record cleaning is for the better - but as RCMs, they are second rate. I say this as an owner. I believe better alternatives are available for the same or lower cosr.
P.S. yiu can put the ADS rollers in a washing machine gentle cycle.  Rinse them thorougly afterwards and air dry.  Keep a spare set of rollers on hand for comparison.