Auto water chang apex Neptune

[Carl C]

Hi I have had the auto water change system for several years now. I am currently running 2000 mL change per day. I suspect that the old water being siphoned out is pulling faster or at an increased volume than the new water coming in from the new water source in the basement. I believed this based on weekly changes in salinity. My solution is to make the new water in the basement have a higher salinity. However, it is still diluting the salinity each week. So I decided to try and have the water being pulled out from the tank be 10% less 1900 mL, thinking pull a little less “old” add a little more “new” it might work out. However, it looks like when I do that the two heads stop spinning at the same time. And then, of course, when they are out of sync, the water being pulled out activates the auto water fill up again, diluting the water salinity. Long story short should I try to calibrate the two head.? I noticed that the head, does sound a bit like it’s not running too smooth, I’ve had that problem in the past, I have replaced heads, and I’ve also replaced the tubes running from the basement, thing is is, I don’t remember if I replaced both of the lines or just one, it is a bit of a hassle to run new lines, I’m wondering if there is just a way to calibrate? I am a bit confused.

 

[sunken3]

I used to use the neptune AWC DOS system but had similar issues. The heads need to be recalibrated every so often (think every month or two) and the heads are supposed to be replaced periodically (like every 6 months or so)... last time I switched them out they were $29 a head. I havent used it in a while, but yes you can calibrate the DOS - i forget, but it was by filling up a 50ml or 100ml vial in a certain amount of time..

 

[All_talk]

How timely, I tried to set up my Apex AWC this weekend and could not get what I feel is an acceptable balance between the In and Out pumps. I was testing with the system plumbed as it would be in use, but with a large graduated cylinder in place of the sump (at the same elevation). I calibrated the pumps with the Task (many times) and set up the AWC through the Task function as well. I did many test runs of several hours and each time the "sump" level changed over the run. My average error was about 3%.

I then decided to make an adjustment in the calibration. I adjusted the measured amount by 3% in the appropriate direction, but this resulted in the balance being off much more that 3% in the opposed direction. I repeated this attempt several times with no success.

Then I attempted what the OP tried, with the same result. Adjusting the total volume added or removed over the time frame (24 hours), resulted in the In and Out pumps running a different schedule. One pump would be pumping a smaller volume more frequently to the others larger volume less often. Again, no solution.

I suspect some of the calibration error is due to the fact the Out pump runs in the opposite direction and the calibration is done at a different speed than the pumps runs during the AWC.

At this point I don't see how the DOS is not going to change the tank salinity over the course of the water change. 3% of 35 ppt is 1.05, so you end at 36 or 34. When I do my current bucket water change I match the volumes very closely and there is no detectable change in salinity. If I can't find a way to adjust the AWC I don't know that I will be able to use it... disappointing.

I hope other users have some solutions.

 

[sunken3]

How timely, I tried to set up my Apex AWC this weekend and could not get what I feel is an acceptable balance between the In and Out pumps. I was testing with the system plumbed as it would be in use, but with a large graduated cylinder in place of the sump (at the same elevation). I calibrated the pumps with the Task (many times) and set up the AWC through the Task function as well. I did many test runs of several hours and each time the "sump" level changed over the run. My average error was about 3%.

I then decided to make an adjustment in the calibration. I adjusted the measured amount by 3% in the appropriate direction, but this resulted in the balance being off much more that 3% in the opposed direction. I repeated this attempt several times with no success.

Then I attempted what the OP tried, with the same result. Adjusting the total volume added or removed over the time frame (24 hours), resulted in the In and Out pumps running a different schedule. One pump would be pumping a smaller volume more frequently to the others larger volume less often. Again, no solution.

I suspect some of the calibration error is due to the fact the Out pump runs in the opposite direction and the calibration is done at a different speed than the pumps runs during the AWC.

At this point I don't see how the DOS is not going to change the tank salinity over the course of the water change. 3% of 35 ppt is 1.05, so you end at 36 or 34. When I do my current bucket water change I match the volumes very closely and there is no detectable change in salinity. If I can't find a way to adjust the AWC I don't know that I will be able to use it... disappointing.

I hope other users have some solutions.

yep. I ended back to the bucket method..

 

[Klyle]

This sucks…I finally got an Apex and went with the DOS bundle for AWCs. I still haven’t calibrated the pumps but it looks like I have a bit of air coming out with the new water. I’m pulling water from the basement also and can see how this is probably going to be an issue. Has anyone been successful with AWCs while not having fluctuations in salinity? I’m going to be pretty disappointed if I have to just use the DOS for alk and calcium.

 

[bushdoc]

I used AWC with DOS for 2 years or so and apart from problems with uneven in/out issues I also had some disconnect and water on the floor.
I found DOS unit to be clunky, noisy, poorly made so it has been banned now my garage. There are different brands of AWC system, but for now I am giving it a brake, perhaps in the future I will try something different.

 

[All_talk]

Follow up…

After reading through this manual: https://www.neptunesystems.com/downloads/docs/DOS_manual.pdf#page6

I have setup my AWC with manual programming (no wizard) and have been able to tune it in so that that the in and out are very even.

I calibrated the pumps first, then set it up to do 5 gallons over 24 hours. I ran it for 5 hours and measured how far it was off (about 1.5%), then adjusted one pump. I then ran it for a few more hours and it was spot on.

So far I have only done a couple of 1 gallon changes but all seems well.

 

[David_CO]

I believe this is more of an issue with the right dosing head wanting to rotate in a reverse direction than the calibration and the pushing/pulling distance being different during calibration than when the AWC is running.

This thread by Suncrest outlines how to have both pump heads move in the same direction so you can calibrate based on actual AWC run distances.

Neptune Apex Tutorials Part 9: DOS

Neptune DOS Tutorial

www.reef2reef.com

I have 3 DOS units and I have found them all to be very reliable in terms of accuracy. I only AWC 7000ml a day, if your trying to do alot more I could see the error margin being more significant.

 

[AJsReef]

Make sure you’re calibrating at the exact length and layout you plan to use. I used DOS for several years without issues with salinity stability.

That said, the past few years I’ve been running Versas as I prefer the silent operation, better calibration (use selectable time/volume) and user serviceable head (tubing) replacement.

Regardless of pump I’d recommend 6-8 weeks per calibration and head replacement within 6 months.