What can bring the Salinity down?

[Ace1]

im having problems keeping my salinity stable, i top off with salt water with a slightly higher specific gravity but it still seems to read lower after a few days. Oh i use the refractometer (the $99) one. any suggestions?

[FOSELONE]

ive read those refractometers need to be calibrated often...maybe you should try a swingarm to make sure theyre both reading the same...

[zeppelin]

Addressing the title of your thread.

You should be topping off with RO freshwater, not saltwater.

When evaporation takes place, water is evaporated, but the salt is not, which will raise the tank salinity level. That raise will depend on your tank size(water volume) and the amount of evaporation per day you are getting. Topping off with saltwater, while replacing the evaporated water, also adds salt and increases the salinity. Hope I am making sense.

Topping off with a higher salinity water is actually increasing the issue. While that topoff saltwater will dilute into the tank water, and make the overall salinity level less than that of the topoff water you put in, your salinity level will still creep up over time as you are increasing the salinity of the tank a little everytime you add more saltwater.

The only time to add saltwater is when you do a water change, as you are then actually pulling the water and all its chemicals and minerals out at the same time, including salt.

Also, if you are adding topoff with a higher salt content as a means of raising your salinity on purpose because it is low, do that carefully, and preferably in the sump, away from any corals.

Salt level should remain constant in a tank unless there is a leak, and you have an RO freshwater auto topoff. In that case saltwater is leaking out and freshwater is being replaced, which would lower your salinity over time.

Hope this helps.

Larry

[Bebo77]

<a href=showthread.php?s=&postid=10198260#post10198260 target=_blank>Originally posted</a> by zeppelin
Addressing the title of your thread.

You should be topping off with RO freshwater, not saltwater.





yup

[Ace1]

All that is understood.... but my readings apear to decreas, so its like im battling to keep it up. RO/ topoff seems to further decrease the salinity. I'll check the calibration again. Oh i have a 34 gallon red sea max.

thanx all

[drummereef]

Use this to calibrate your refractometer and check back. ;)

Reef Aquarium Salinity: Homemade Calibration Standards
http://reefkeeping.com/issues/2004-06/rhf/index.htm

[Hypertek99]

If you are trying to bring it up then add more salt to your topoff if you are trying to bring it down then just add fresh water.

[zeppelin]

If topping off with R/O freshwater is lowering your salinity, then you have to have a leak somewhere. Saltwater is leaving your system, and being replaced with freshwater. Thats really the only reason I can come up with for the salinity level continually decreasing. Sorry I couldn't be of more help.

[Hypertek99]

I think your refractometer is broken. Try a cheap swingarm one.

[Ace1]

Naw i could be that it is an enclosed system, so the salt could be depleting (if that makes any sense??) but i do get salt deposits on the inner hood very often?? Im running the red sea max 34 gallon..

thanx all

[John Zillmer]

Salt leaves the system via skimmate, too.

[grallster]

Yeah, if you're dumping alot of skimmate and skimming wet it will take a toll on the salinity.

[lpsluver]

<a href=showthread.php?s=&postid=10209630#post10209630 target=_blank>Originally posted</a> by grallster
Yeah, if you're dumping alot of skimmate and skimming wet it will take a toll on the salinity. If his RSM skimmer is producing that much skimmate then it woud be a first for that skimmer. These skimmers are notorious for how ineffective they are, at the moment.

Just "field" calibrate the refractometer with RO water (resets to 1). This should be good enough to give you an idea. Swing arm hydrometers suck and can provide you with enough bad information to make things even worse.

[storrisch]

I prefer the glass hydrometers.

What is your salinity in the tank right now?

[seapug]

Something is wrong with your refractometer. It is physically impossible to top off with saltwater and get a lower salinity reading unless you have stalactites of salt creep around your tank.

Get a cheap swing arm, get the Salinity where you want it, then, to make your life easier, make some sort of waterline mark and top off with FRESH water as needed to keep the water level at that mark. After that you can put the hydrometer in storage. I don't even use mine when mixing saltwater anymore.