Salinity, 2-part dosing and small tanks

[hobbzz]

I'm dosing with Randy's 2 part and it significantly increases the salinity in my 20g (about 27g tsv). Anyone know of an online calculator or formula for adjusting salinity when dosing with a home made 2-part?

 

[Paintbug]

couple of questions for you. first are you testing the SG with the water level in the tank the same? a little evaporation will make the SG jump in a small tank. if thats not it, what are you using to test the SG? if you are using a refractometer then thats not going to be the problem. the last question is did you use RO water to mix up the 2 part?

i have been using Randy's recipe for almost 2 years. I have never seen it raise the SG any in either of my tanks, the 75g, or the 20g frag tank.

 

[hobbzz]

I measure after topping off, with a refrac. Water level is the same in the sump when I test. I mixed the 2-part with distilled water. I tested the 2-parts with the refrac, and they were both off the top end of the scale (recipe #1). I would say that maybe I mixed the 2-part wrong, but my CA and ALK are in check when adding the proper amounts of the parts so that's not it. I run my skimmer 24/7 and have a whisper air pump feeding two air stones in my sump due to my apartment being sealed up all the time (hence low ph), which would add to evap. Other than that, nothing special. I'm going to start a log every day to see how much it changes, but I was just curious to see if there were any sites with something like that. I'm also awaiting parts for an alk drip, and if that works well, I will use the same thing for an ato. But the question still stands.

 

[burris]

You can calculate the percentage change in salinity you want, then remove that much salt water from the system and replace it with fresh water. That will bring your salinity back but you have to do water changes to bring the ionic balance back.