Mag/alk/Ca relationship... getting the numbers up?

[cr500_af]

First, Happy Thanksgiving!

Now, to the issue...

I am having a heck of a time keeping my Ca/Alk/Mg up... or rather, getting them where I want them.

Currently at:
Ca 400ppm
Mg 1170ppm
Alk 3 meq/l
using Seachem reef salt and BRS supplements

I read some time ago a post in someone's thread (I think it was by Danny Bradley) where a simple explanation of the relationship between the three was given, i.e. if "a" is low then "b" will be hard to get in line. I've searched and come up dry.

As a background, for a while I've been testing these parameters every week or two and then dosing based on the BRS calculator. I know, that's not attentive enough. Over the last week I've been more on top of things, and testing/dosing daily.

In a week, I've only managed to raise Ca by 50ppm, Mg by 20ppm and alk by .5 meq/l. Since my alk is the farthest from the target, I've been on it the hardest.

I've been dosing the max amounts of everything except mag, because I'm milking what I have left until my new batch arrives... out of the 12 oz/day max, I'm using 8 oz/day. In addition to the BRS stuff I'm using Seachem Reef Builder in my ATO water in the concentration they recommend.

I don't have a particularly calcium hungry tank... I have about 15 SPS frags (but they are small frags except one or two), two small (3-4") colonies and a smallish clam (3.5"). I know I'm using a bit, but I can't imagine that dosing won't keep up with that load.

Any advice is VERY appreciated.

 

[schwaggs]

I believe the rule you are looking for is Mg at 3 X the CA level you want. So if you want to keep your CA at ~400, your Mg should be at least 1200.

FWIW, I had a heck of a time keeping both CA and Alk up with the 2 part solutions. I could boost one but the other would fall. This was with a decent Mg level... only after adding a CA reactor did it become easy for me...

 

[cr500_af]

I have a Ca reactor in the works, but it needs a leak or two fixed before I can use it (which involves ordering a pump part), so I'm figuring two weeks before that is on line. Plus, I know I need to get the level right so the reactor can maintain it rather than raise it.

 

[tdwyatt]

Just curious, which Seachem salt are you using, and how are you testing for your alk levels?

Have you tested for borate alkalinity? (there is a seachem test kit for this)...

Also, do you perform water changes, if so, how much and how often?

How have you been supplementing your hermatypics (Ca++ and HCO3- and MG++)? How much have you used over the last 6 months?

 

[cr500_af]

tdwyatt;421706 wrote: Just curious, which Seachem salt are you using, and how are you testing for your alk levels?

Have you tested for borate alkalinity? (there is a seachem test kit for this)...

Also, do you perform water changes, if so, how much and how often?

How have you been supplementing your hermatypics (Ca++ and HCO3- and MG++)? How much have you used over the last 6 months?

I'm using Seachem Reef Salt. I test for alk with a Seachem "multi test" for pH and Alk (though I only use it for alk; I have a pH monitor). If this is a different test than for borate alk, then no, I haven't.

I do approximately 15g every two weeks on a 90g DT/30g sump, of which the sump is filled to about 15g. So, 105g less the rock displacement system volume.

And, not trying to sound too ignorant about the hermatypics (as I've never even heard that word before!), but the only supplements I use are The BRS "recipe 1" two-part and the mag solution is a blend of their two types of magnesium. The Seachem Reef Builder I had from before, and just started using it in the ATO as what I was doing wasn't cutting it.

I haven't been dosing with this for 6 months yet (and I don't remember when I started... maybe 9 weeks? I started with BRS when I got more into SPS) but I have used approximately 1/2 gallon each of Ca and Alk, and there is only about a cup left in the jug of Mag solution.

Thanks for the reply.

 

[hackman72]

I had the same problem. CA held steady at 350ppm, MG steady at 1075, and alk @ 2.75 meq/l. I followed everyones advice, searched threads and read labels and couldn't get an increase to save my life. I have a 120 gal w/30 gal sump for a total system water of 99 gallons after displacement. I made up 50 gallons of water as my emergency water and let it sit at those levels in case my experiment started to go bad and also had my QT up and running.

(Here's where I get blasted for not going slow)

Everyday, I added all 3 in larger than recommended quantities. I add SeaChem Reef Builder twice a day, each time adding the recommended dose for the whole day...(basically a daily dose every 12 hrs). I dripped kalk all night and mag all day that were also doubled and made up from aquarium water.

It took a little over a week to get the numbers up but, I went back to a regular schedule with a little extra in each drip or dose and my numbers stay pretty consistent now. I kept a very watchful eye on everything and nothing seemed to be stressed or came up missing. I have better growth now and things appear to be running much smoother.

 

[weaglereefer]

Found this page very helpful and bookmarked a while back.