Cal Alk and mag

[Pcreefer]

i been trying to get my parameters stable just can't I have 350 gallon do about 100 gallon water change monthly use reef crystal s salt I have dual Mrc calcuim reactor that I trying to set up once I get my levels higher I been dosing to get them higher with no luck what's my options to get a stable tank I have mostly lps some sps and softies

 

[twilliard]

When you say can't get them stable what are your current numbers like?

 

[Pcreefer]

Alk 7 mag 980 cal 380 just got back from vacation did 100 gallon water change and those are my current reading gonna retest tomorrow

 

[twilliard]

Do you have a dosing system set up?

 

[Pcreefer]

No I add liquid cal Alk and mag daily manually at night and test next day

 

[twilliard]

The low magnesium will be an issue to stabilize your numbers.
Randy will have more insight on how this is happening and methods to correct.
But in my opinion dosing needs to be brought up with magnesium as it is a net to hold the numbers together.
Work with the water you have. Hold off on the water changes till your dosing can catch up.
(Bad batch of salt? I wonder) that magnesium is way low

 

[Downbeach]

What is your salinity? What are you using to measure it with? If its a swing arm type hydrometer, or an improperly calibrated device, it may be giving you bad readings, causing you to add too little salt mix, and by extension too little Ca,Mg and Alk. RC should be mixing up to a Mg level of ~ 1450 @ a SG of 1.026(35ppt).

 

[redfishbluefish]

Agree with @Downbeach....something is not right with your mag number....can't see it being that low with RC. Have someone else verify your salinity and test for alk, calc and mag using their kits.

 

[Pcreefer]

I using a device calibrated with tap water all double check with a swing arm type I use salifert test kits and Red Sea salt levels are 1.027 gonna retest everything again today

 

[Downbeach]

What device are you checking with tap water? If its a refractometer you should be using a calibration solution that is close to the refractive index of the sample you are testing.

 

[Pcreefer]

Ok I'll have to get some just checked with the swing arm one I was at 1.025

 

[Randy Holmes-Farley Verified Community Expert]

Even with the potential to be slightly off in salinity, the magnesium number is still so low it seems an error.

I would not add more magnesium until you confirm with a different kit somehow.

 

[GainesvilleReef]

How do you mix your new salt water? Are you heating it during mixing? Are you getting a lot of precipitation?

 

[Randy Holmes-Farley Verified Community Expert]

FWIW, even if every bit of alkalinity in Reef Crystals (at, say 11 dKH) was used to precipitate magnesium carbonate, you'd only drop magnesium from about 1400 ppm to 1352 ppm (and, of course, that couldn't happen since calcium carbonate will predominate any precipitate.

 

[Pcreefer]

I'm gonna test again I'm using salifert and Red Sea test kits I'm mixing it on brute 55 gallon barrels mix salt 3 hours or so and I don't heat the water it's the same as my tank

 

[GainesvilleReef]

How warm is your tank and mixing water?

 

[twilliard]

I have had plenty of times where the RC would mix to 7 DKH
(Switched cause of that)
Test again your magnesium
Thinking that's what your salt batch mixes at

 

[GainesvilleReef]

I use regular IO and have never had it mix that low. I did have problems RSCP if I heated it too soon after mixing do to precipitation.