Neptune Dos

[aggrofish]

So this might be a stupid question but I can’t seem to figure out whether or not both pumps work at the same time, whereas they remove and add new water, or they are staggered where it removes X amount then adds?

 

[iamacat]

If it’s AWC they will run together same time.

 

[jsker]

If it’s AWC they will run together same time.

+1 and depending how the pumps are calibrated, one might run a little longer. I had this happen when I ran a DOS.

 

[((FORDTECH))]

I have 2 systems both with dos auto water change and both system one of the pumps run for like 2-3 seconds longer each time

 

[aggrofish]

So then to not mix the old/new water you're limited by the capacity of your return chamber?

 

[Flux Capacitor]

If you set it as an AWC you will always lose a percentage of the new water going in, but it’s very very small. Good write up about the loss, and other auto water change information here:

http://reefkeeping.com/issues/2005-10/rhf/index.php
To get the best results have the old water being taken out in the first chamber, and add the water back to the last chamber.

 

[aggrofish]

Thanks, I'll give it a read. I'm guessing manual would be for larger changes. Shutting down the return, filling the sump, removing X and replaying with Y.

 

[Flux Capacitor]

Correct, you could set the dos to do that as well, taking water out and then adding it back, but it will require the pumps to be running at a higher speed and will be louder. With the amount of loss you get from doing it constant it really has no benefit to setting it up that way.

When I need to do heavy cleaning of the tank I do a manual water change with a 32 gallon brute trash can separate from the auto water change system set up. I don’t do this often though.

 

[aggrofish]

Correct, you could set the dos to do that as well, taking water out and then adding it back, but it will require the pumps to be running at a higher speed and will be louder. With the amount of loss you get from doing it constant it really has no benefit to setting it up that way.

When I need to do heavy cleaning of the tank I do a manual water change with a 32 gallon brute trash can separate from the auto water change system set up. I don’t do this often though.

What percentage are you changing daily? I'm setting up a new to me reefer 350 and experimenting with daily water changes in my 45G AIO. I've got everything where I want it calcium 440, Mag 1450, Alk 10.5 (what the current batch of IO mixes at), Nitrate ~10-15 and phosphate at .05 - .07. I want to see what affect smaller changes have on the parameters and dosing.

 

[Flux Capacitor]

I have a reefer 525xl I change 1 percent per day so 5250ml. I do have a custom program on mine instead of using the wizard, but it’s so that the pump runs at the slowest speed during the day and then catches up with the rest of the water change while we sleep at a higher speed.

Since your tank is smaller than mine you could use the wizard and change 3350ml a day, which is just below 1 percent for you, and it would run the slowest pump speed keeping the noise of the pump quiet and you wouldn’t need a custom program.