DOS head clicking + Running different length of time + Water Change Intervals

[reefdiver73]

Three Neptune Apex DOS questions in one post. Hope that's ok.

1) One of the DOS heads is suddenly clicking. Defective head? What can I do about it?

2) The DOS pumps are running different durations of time during automatic water change where the two should each be moving the exact same amount of water. Is their calibration possibly that much different to achieve the same end result? 11 extra seconds on one side vs the other roughly on a 225.3ml water change (5 gallons, or 18927ml per 24 hours divided into 84 water changes per day)

3) Can I force the DOS to do fewer water changes but still achieve the target of 5 gallons in 24 hours (without taking hours away from it)? For instance, run the pump twice as fast but only do it twice per hour -- or maybe 4x as fast (if that's possible) but only run approximately once per hour? I really don't like hearing it run almost 4x/hour. I just used the wizard and that's what it came up with.

Video of the clicking and run time difference. About 12 seconds in you'll hear the clicking stop and you'll hear the tone of the DOS change as the one dos pump stops earlier than the other:

 

[P-Dub]

Three Neptune Apex DOS questions in one post. Hope that's ok.

1) One of the DOS heads is suddenly clicking. Defective head? What can I do about it?

2) The DOS pumps are running different durations of time during automatic water change where the two should each be moving the exact same amount of water. Is their calibration possibly that much different to achieve the same end result? 11 extra seconds on one side vs the other roughly on a 225.3ml water change (5 gallons, or 18927ml per 24 hours divided into 84 water changes per day)

3) Can I force the DOS to do fewer water changes but still achieve the target of 5 gallons in 24 hours (without taking hours away from it)? For instance, run the pump twice as fast but only do it twice per hour -- or maybe 4x as fast (if that's possible) but only run approximately once per hour? I really don't like hearing it run almost 4x/hour. I just used the wizard and that's what it came up with.

Video of the clicking and run time difference. About 12 seconds in you'll hear the clicking stop and you'll hear the tone of the DOS change as the one dos pump stops earlier than the other:

1) Mine does the same and I'm not worried. Been that way for almost a year.

2) Could be. One that is pumping saltwater and one fresh. Different densities. Is that is enough to account for the difference... ? Recalibrate and see if things change. When was the last time you recalibrated? For good measure every 6 months or so or whenever there is a change in tubing, liquid.

3) Yes you can. I have mine perform it every day beginning at midnight so I don't have to listen to this rather loud piece of equipment. I change 2.5 gallons every day. Your run time may differ due to the larger volume of water. The DOS only runs at certain intervals and associated speeds to meet the time frame you select. If it can't do your volume in the selected timeframe it will tell you. just increase the duration of the water change.