A question for fellow 2-part Ca/Alk users

[Mike O'Brien]

<a href=showthread.php?s=&postid=8363292#post8363292 target=_blank>Originally posted</a> by Hef
I've never heard that. How can putting Baking soda and CaCl in your tank raise your Salinity?

From all the sodium from the baking soda, and the chloride from the calcium chloride.

It will raise salinity, but so will all the other two part product's that are maketed. I've not noticed anything significant. I still add salt water to replace what was skimmed, and I've never had to lower my salinity.

 

[RobTheReefer]

You guys must not be adding much of it...

Anyway, here it is, right from the horses month:

http://reefkeeping.com/issues/2006-02/rhf/index.php

Residue Remaining from Recipe #1 when using Recipe #1, Part 3A

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).

 

[seattlerob]

I guess the reason my salinity stays constant is due to the fact I don't go a year without water changes

I change water on a regular basis (like most folks do I'm sure) and I test both the salinity of the new salt water before adding, and also the salinity of the tank after the water change.

Even if I was not using Randy's DIY 2-part additive (i.e. using a carx or using a retail product), I think it's prudent to do regular water changes, and to check salinity on a regular basis. Next to temperature, I find monitoring and keeping salinity in check the easiest of the things I test for.

 

[Hef]

I guess that should have been the obvious response. Of all the things in this hobby we labor over, Salinity is the easy one.
How can you continue to dump something in your tank, without doing water changes - which of course includes, checking the salinity of the new water and the tank water.

I dose about 180ml of both alk and Ca per day. Mg very rarely.

 

[johns]

I add 250mls of each part every day into a system of roughly 90 gallons (and this is using the more concentrated recipe 1). I have seen the notes about salinity increase and the reasoning seems sound. But I have checked my SG after each water change and right before the next one (anywhere from 2 - 4 weeks between changes), and I have never noticed a change in the SG.

If someones salinity changed drastically over a short time, I have to assume it's not due to this dosing but that something else went wrong.

 

[DaddyJax]

<a href=showthread.php?s=&postid=8358943#post8358943 target=_blank>Originally posted</a> by Tutmos
Better option yet, switch to Randy's and save up $100 for a medical dosing pump that can automate dosing of both, no CO2 can to muck with.

Kevin W.

My thought exactly!

 

[RobTheReefer]

<a href=showthread.php?s=&postid=8378627#post8378627 target=_blank>Originally posted</a> by Hef
I guess that should have been the obvious response. Of all the things in this hobby we labor over, Salinity is the easy one.
How can you continue to dump something in your tank, without doing water changes - which of course includes, checking the salinity of the new water and the tank water.

I dose about 180ml of both alk and Ca per day. Mg very rarely.

You're right. If people have time to dump a little of this and a little of that every time they walk past their tank (shockingly, some people admit to doing just that :eek1: ), then maintaining their tank's salinity in going to be a cake walk.

I remember reading one the the TOTM issues, where a reefer, who used a two-part dosing method, had to set up a seperate dosing pump to continuously dump tank water and replace with RO water to keep his salinity in check.

 

[dvanacker]

The tank that your are describing probably has tank water being replaced with chloride free synthetic sea water.