Magnesium Levels

[Adriifu]

Hi! I’ve got a 26-gallon saltwater reef tank. I have pulsing Xenia, a torch, Duncans, mushrooms, a joker Favia, and a Christmas Favia. There’s also a royal gramma, two snails, and a pistol shrimp/watchman goby pair. I’m planning on getting a clownfish pair and maybe one more fish as well as more coral. For now, though, I was wondering whether I need to add magnesium supplements to the water. I tested it today and it seems to be around 1,230 ppm. My calcium levels stay around 400 ppm and my alkalinity tests between 180-240 ppm with test strips (hard to tell). I change about 25% of the water every Sunday using Instant Ocean salt. I’m planning on mostly keeping soft coral in this tank, and I have been loving the pulsing Xenia lately, so I will definitely be looking into getting a similar species. Until then, do I need to do anything for the water regarding magnesium, calcium, and alkalinity levels, or is everything where it needs to be? I’m specifically asking about magnesium because I feel as if it’s a bit low. Thank you!

 

[GoVols]

JMO...

I'd slowly raise your mag to 1250 - 1350ppm, and keep mine at 1400. Don't let it get below 1200 ppm.

Looks like your parameters are close to what IO mixes too.

FWIW:
I would not use test strips for any parameter, or any test strip brands. Test strips are not accurate.

If you can, buy the Hanna alk dkh checker. It's pretty much spot on and easy to preform.
https://www.bulkreefsupply.com/alkalinity-dkh-colorimeter-hi772-hanna-checker-marine-water.html

Refills
https://www.bulkreefsupply.com/hi772-26-alkalinity-checker-reagents-hanna.html

 

[Adriifu]

JMO...

I'd slowly raise your mag to 1250 - 1350ppm, and keep mine at 1400. Don't let it get below 1200 ppm.

Looks like your parameters are close to what IO mixes too.

FWIW:
I would not use test strips for any parameter, or any test strip brands. Test strips are not accurate.

If you can, buy the Hanna alk dkh checker. It's pretty much spot on and easy to preform.
https://www.bulkreefsupply.com/alkalinity-dkh-colorimeter-hi772-hanna-checker-marine-water.html

Refills
https://www.bulkreefsupply.com/hi772-26-alkalinity-checker-reagents-hanna.html

Thanks! I purchased Seachem’s magnesium supplement. I’ll add it the next time I top off water. Should I look into getting a different type of salt? Maybe one that is specific for reef tanks?
I’m aware about the inaccuracy of test strips. I just can’t currently afford a test kit for alkalinity. I recently bought one for magnesium only two days ago. This is all I had.

 

[GoVols]

Should I look into getting a different type of salt? Maybe one that is specific for reef tanks?

Well,
Instant Ocean is just about the cheapest mix, but it's always been kinda low on cal and mag, but high on alk.

The Red Sea "Blue Bucket" mixing parameters are pretty good to my taste, but it will cost more than the IO.

 

[Austin Lee]

If you're budget concious, IO Reef Crystals is decent and has higher nutrient levels.

 

[Adriifu]

Okay, thank you! I’ll go ahead and get a new reef salt as soon as I can.

 

[Austin Lee]

Okay, thank you! I’ll go ahead and get a new reef salt as soon as I can.

((Just a note on that)) Do some research on which salt matches your nutrient level goals. If you have a salt that mixes at 480 CA, for example and your goal is 475 - that's a good option. If it mixes closer to 400 or 425 (I'm just making these numbers up), it's not a good option.

The closer your salt mixes to your goals, the less you have to dose. It'll likely end up saving you money in the long run.

 

[Randy Holmes-Farley]

Raising the salinity is likely the best answer. Magnesium is not low in IO, and low magnesium may just mean low salinity.

 

[Randy Holmes-Farley]

Okay, thank you! I’ll go ahead and get a new reef salt as soon as I can.

That’s a fine, but unnecessary option. IO is perfectly fine.

 

[Adriifu]

((Just a note on that)) Do some research on which salt matches your nutrient level goals. If you have a salt that mixes at 480 CA, for example and your goal is 475 - that's a good option. If it mixes closer to 400 or 425 (I'm just making these numbers up), it's not a good option.

The closer your salt mixes to your goals, the less you have to dose. It'll likely end up saving you money in the long run.

All righty, thank you

That’s a fine, but unnecessary option. IO is perfectly fine.

My specific gravity stays around 1.025.

 

[Randy Holmes-Farley]

All righty, thank you

My specific gravity stays around 1.025.

Up it to 35 ppt (1.0264) and magnesium will jump by about 70 ppm.

 

[Adriifu]

Up it to 35 ppt (1.0264) and magnesium will jump by about 70 ppm.

All right, I’ll start doing that. Thank you!

 

[RossV]

If you're budget concious, IO Reef Crystals is decent and has higher nutrient levels.

Hopefully not nutrient levels...