Please help me understand my water

[agiacosa]

Hi,

This is a new tank that has cycled. Here are my water parameters as measured this morning:

Temp: 78F
Salinity: 1.025
pH: 8.3
NH4: 0
NO2: 0
NO3: 0
KH: 9.3
PO4: 0.5
Mg: 1500+ (didn't change color at max Salifert test)
Ca: 490

I use Tropic Marine Pro salt with RO/DI that measured 0 TDS as final product prior to adding the salt. The test kits are all brand new Salifert test kits. At this point, I have not supplemented with anything but bacteria via Zeovit.

The parameters seem out of whack to me. I don't understand why I'm showing so much Mg. Also, I'm planning to keep SPS and would like to get these numbers down to natural seawater. Any ideas on how to do that?

Thank you!

 

[Randy Holmes-Farley]

If you've not added a lot of magnesium, I wouldn't worry about it. . Probably some testing error or inaccuracy. Magnesium does not rise on its own, and that salt mix does not have that much, typically. Even if it is that high, it is not likely any concern.

I'd focus my concern on the 0.5 ppm phosphate which will drive algae and will be difficult for calcifying organisms like hard corals.

 

[agiacosa]

Thanks, Randy. PO4 is something I know how to deal with.

 

[Randy Holmes-Farley]

:thumbsup:

Good luck and happy reefing.

 

[agiacosa]

Well, wanted to update and ask a question. Today, my parameters are:

Temp: 78F
Salinity: 1.025
pH: 8.3
NH4: 0
NO2: 0
NO3: 0
KH: 8
PO4: ~0.03
Mg: 1500+ (didn't change color at max Salifert test)
Ca: 500

I did a 20% water change and I presently have three SPS corals and one ricordea in the tank. Oh, five Turbo Snails also.

My Alk seems to have come down 1.3 ppm but my calcium has gone up 10 ppm? Mg hasn't changed. PO4 way down

I'm trying to understand why Alk dropped so much but calcium and Mg stayed about the same. I haven't dosed anything except Zeovit.

The aquarium was used and had a lot of dead coralline algae on the back wall. Could this have dissolved into the water providing Ca and Mg to the water thereby resulting in my elevated numbers?

If not, what's up? Should I dose alk only?

Thanks in advance.

Art

 

[Randy Holmes-Farley]

The alkalinity reading may be real, but a drop of 10 ppm is within the noise of testing, and the water change allows the alkalinity and calcium to move independently, depending on what is in the new water. So I would not pay any attention to them going in different directions, or draw any conclusions based on a 10 ppm calcium "change".

Could this have dissolved into the water providing Ca and Mg to the water thereby resulting in my elevated numbers?

Nope. It won't dissolve, and if it did, you notice the effect on rising alkalinity before calcium or magnesium as it adds a lot of that too.

 

[agiacosa]

Thanks.

 

[Randy Holmes-Farley]

You're welcome.

Happy Reefing.