Can I use a dosing pump to remove water from the display to counteract increased salinity from 2-part?

[jnh427]

As the title says, I would like to eventually get to a place with my tank where I don't need to rely on regular water changes, even if this is a year or two down the line. I know that dosing two part raises the salinity over time. To correct this, could I have a dosing pump moving a set amount of water from my display to a drain every day? Combined with an ATO of course.

 

[P-Dub]

As the title says, I would like to eventually get to a place with my tank where I don't need to rely on regular water changes, even if this is a year or two down the line. I know that dosing two part raises the salinity over time. To correct this, could I have a dosing pump moving a set amount of water from my display to a drain every day? Combined with an ATO of course.

You certainly could. It will take some tinkering and adjusting over time to get it right. Basically, I do the same thing but opposite. I set a daily AWC with my Neptune Apex. I was having the opposite issue with my salinity dropping due to wet skimming. I do not dose but have a CaRX. So, I now add more new salt water every night to combat the salinity drop. Took a few iterations to get it right. So long as you maintain your home environment to not impact evaporation you can get this to work.

 

[Randy Holmes-Farley]

Yes. I used a similar setup for Automatic water changes, using a dual head pump, one sending water in and the other taking it out.

i was changing about 3 gallons a day, so much more than you would need for this purpose, so would use a much slower pump, or better, on a short timer.

 

[Randy Holmes-Farley]

If you use my DIY (ala BRS, etc.), then the info below can be a rough guide to how much you need to remove:

After one year of adding 8 ppm of calcium and the accompanying 0.4 meq/L (1.1 dKH) of alkalinity per day (41 mL of both parts per day or 4 gallons of both parts per year in a 50-gallon aquarium, including the effect of the magnesium part #3A, 2440 mL/year), the following residue (Table 2) would remain after calcification and adjustment for salinity (there is roughly a 32% rise in salinity over a year using this addition rate without water changes).

Thus, if dosing 1.1 dKH per day, you would export roughly 32% of the tank volume in a year, or 0.09%/day.