2-part dosing and salinity

[animan]

Ever since I started dosing b-ionic I have noticed that my salinity has been creeping up.. normally it is rock solid at 1.025 since I have an auto top off unit.

Does two-part dosing cause increase in salinity? If so, how best to compensate for it.

Thanks in advance.

[jansenwrasse]

Routine water changes should allow you to comensate for monthly increase. I make new water to 1.025 (low demand system) and allow it to raise to 1.0265 :)

Hope this helps :)

[drparker]

When mine creeps I pull a cup of water out of the sump so the ATO puts in a little extra fresh.

[animan]

Thanks for the suggestions guy. I will give them a try.

[Randy Holmes-Farley]

I discuss the salinity rise here:


How to Select a Calcium and Alkalinity Supplementation Scheme
http://www.advancedaquarist.com/issues/feb2003/chem.htm

from it:

The rise in salinity of these products over time can be very roughly calculated, though there are several reasons why this calculation is only an estimate. For every 1000 meq of alkalinity added in this fashion (and the matching amount of calcium) these products will deliver on the order of 60 grams of other ions to the tank. In a tank with a low calcification demand (defined later to be 18.3 thousand meq of alkalinity per year in a 100 gallon tank (50 meq/day)) this effect will raise the salinity by 3 ppt per year (compared to a normal salinity of S ~35). In a high demand tank (defined later to be 219 thousand meq of alkalinity per year in a 100 gallon tank (600 meq/day)), the salinity will rise by 35 ppt in a year, or approximately doubling the salinity. Consequently, the salinity should be monitored closely in using these types of additives, especially in a tank with high calcification rates.

[animan]

Thanks for the explanation Randy. Luckily my system is not high-demand type, though I saw almost a 1ppt raise over the last two weeks... must be due to something else. I will keep an eye on it and ajdust at weekly water changes.

[Randy Holmes-Farley]

:thumbsup:

Happy Reefing. :)