They may be talking about using the smart dosers as they call them for water change. They will not work currently in the auto water change regimen but I have a Minnow that I currently do water changes with and I have a dosing schedule created and have an output setup to halt the ATO output during the water change. I have done up above 4500ml a day with it but currently I have scaled way back due to very low nitrate readings. Below are the fill and drain pump output settings. Those are fairly simple. They are the smart doser type. They are set to 55ml a minute for this use which is the max for these pumps. Since I use these for auto water change I don't use the reservoir level setting.
This is the output used to halt the ATO output when either the fill or drain pump are running.
Below is the schedule used for the water change. Right now it is set to 600ml a day but that is not my normal amount. Right now I have very low nitrate levels so I have the water change scaled way back. It is split into 4 seperate changes that happen after a alkalinity test is done and before dosing is done.
Below is the ATO output that is halted by the output ATO OK listed above. I use a generic output type since I have several inputs that control whether a ATO is done or not. The depends on settings is where the output listed above is used to halt this output. There is a minimum off time setting on this outpit and when using depends on to turn off the output will halt the minimum off time counter until the depends on is released. So any delay between the drain and fill pump will not be able to turn this output on unless it last at least the minimum off time which it does not. Also there is a sensor in the fresh saltwater reservoir that will halt the schedule if it is low using another output and the depends on in the schedule settings. There is enough water after the sensor goes dry to finish one water change so there should be no issues with it running out before the schedule halts.