Can't get Mg up

[Capsle]

Hey Reefers,

So I've been trying to get Mg up now for a week. My Mg was at 1140 ppm. Salinity was low at 1.022-023 so I've been ATO with 1.030 water for the last week and salinity is only at 1.024.

I've also been dosing Brightwell Aquatics Mg supplement for the last 3 days (2 tsp in 8oz of RODI) and Mg is only up to 1200.

Everything else checks out and just wondering if this is normally this slow.

My current parameters
Salinity 1.024
PH 7.9
Ammonia 0
Nitrite 0
Nitrate 5-10
Cal 450
Also 10.5
Mg 1200.
PO4


Sent from my iPhone using Tapatalk

 

[Entacmaea]

Slow is good ; )

 

[NeilFox]

You can go faster than that. Around 1300 is pretty good. Keep in mind it takes a lot of magnesium to raise it 100 ppm. A 100g tank has over a pound of Mg disolved in it. Magnesium is pretty forgiving. Try dosing a tsp (5ml) in 6oz of RO. Wait about an hour and test it again. I would bring my Mg up to around 1300 to 1350 like this or maybe over the weekend. Raising that much won't hurt anything. BRS has a video about dosing 2 and 3 part. He basically overshoots it and lets it come down on it's own over time. My understanding is too high of Mg (over 1800ppm) causes problems with snails and other inverts.

Alk is a different story all together. You want to go slow with alk changes. SPS in particular don't like alk swings.

 

[Capsle]

You can go faster than that. Around 1300 is pretty good. Keep in mind it takes a lot of magnesium to raise it 100 ppm. A 100g tank has over a pound of Mg disolved in it. Magnesium is pretty forgiving. Try dosing a tsp (5ml) in 6oz of RO. Wait about an hour and test it again. I would bring my Mg up to around 1300 to 1350 like this or maybe over the weekend. Raising that much won't hurt anything. BRS has a video about dosing 2 and 3 part. He basically overshoots it and lets it come down on it's own over time. My understanding is too high of Mg (over 1800ppm) causes problems with snails and other inverts.

Alk is a different story all together. You want to go slow with alk changes. SPS in particular don't like alk swings.

Thanks for the info. I've been dosing 2 tsp (10 ml) in 8 oz of ro water every day. I just don't understand what is using up the mg if anything. Alk and cal are always stable 10.2-10.5 and cal 420-450.