Salt raising alkalinity and calcium exponentially

[bingus]

Every week when I do my water change my dkh goes up about 3 points every time. I test every other day and usually my alk is about 10.5 the day before water change and after it goes up to 12.5~. I use instant ocean reef crystals. Anybody else have this problem? I don’t dose anything for alk or calcium because it’s already so high. I use Red Sea test kits. Any recommendations for new salt?

 

[PanchoG]

Every week when I do my water change my dkh goes up about 3 points every time. I test every other day and usually my alk is about 10.5 the day before water change and after it goes up to 12.5~. I use instant ocean reef crystals. Anybody else have this problem? I don’t dose anything for alk or calcium because it’s already so high. I use Red Sea test kits. Any recommendations for new salt?

Very weird, I use Red Sea Pro salt in my case. You may want to take water from your tank to the LFS to double check your readings.

 

[Shirak]

Every week when I do my water change my dkh goes up about 3 points every time. I test every other day and usually my alk is about 10.5 the day before water change and after it goes up to 12.5~. I use instant ocean reef crystals. Anybody else have this problem? I don’t dose anything for alk or calcium because it’s already so high. I use Red Sea test kits. Any recommendations for new salt?

Have not used it but I would double check your salinity of the freshly mixed SW and then check the Alk with your test kit. I also wonder what % you are doing for a water change to cause it move so much.

Personally I use HW Marinemix Reefer because it mixes around 9dkh which is where I like to run my tanks. So if you decide to switch salts find a quality one that is around the dkh you want for your system IMO.

 

[bingus]

Have not used it but I would double check your salinity of the freshly mixed SW and then check the Alk with your test kit. I also wonder what % you are doing for a water change to cause it move so much.

Personally I use HW Marinemix Reefer because it mixes around 9dkh which is where I like to run my tanks. So if you decide to switch salts find a quality one that is around the dkh you want for your system IMO.

I’ve been doing 15gallons out of a 55g tank

 

[Shirak]

so 55g tank which isn't holding exactly 55g (less because of rock etc) so estimated around 30% water change each week? If so the dkh of your new SW for the water change would have to be around 18 to bump the tank up 3 points!
Are you testing for alk after everything is clear and settled after the water change? Possible you are testing with some suspended fine particles of calcium carbonate or something in the water after doing the water change which could mess up the test?

 

[Backreefing]

Death crystals are well known for ridicules high alkalinity. Switch salt mix and be happy. I use Red Sea blue bucket. Mixes to my parameters. Cheers

 

[mdb_talon]

Does not sound right unless you are using ttapwater or doing over 50% water changes? That salt mix is high in alk, but should not be that high.

 

[Backreefing]

Useing that salt mix ( reef crystals ) I would be checking magnesium to . I got a batch of death crystals that shot my magnesium so high I couldn’t measure it . So ....

 

[NeonRabbit221B]

2nd salt thread tonight which is odd..

RC mixes high which is great in some cases. Double check scale and calibrate refractometer.

 

[Randy Holmes-Farley Verified Community Expert]

Useing that salt mix ( reef crystals ) I would be checking magnesium to . I got a batch of death crystals that shot my magnesium so high I couldn’t measure it . So ....

No need for hyperbole on a mix you may not prefer, but which vast numbers of reefers use just fine.

 

[Randy Holmes-Farley Verified Community Expert]

Does not sound right unless you are using ttapwater or doing over 50% water changes? That salt mix is high in alk, but should not be that high.

I agree. With that size water change, either the salinity measurements have some substantial error, or the alk in the new salt mix is super high, which can happen when using tap water that contains its own alkalinity.