please explaine magnesium testing and why..

[markl]

i always test ph,cal,and alk . people keep telling me to test magnesium. whick kit are you using and what do you dose it with.

 

[dannybradley]

Calcium ions and carbonate ions are essentialy non-reactive with magnesium. Magnesium will bond with carboantes, but will seperate at a pH above 8.0.

Because of this, magnesium acts as a buffer between calcium and carbonates. Instead of bonding and percipitating out, they repel each other. Magnesium is also deposited in the coral skeleton. When calcium reacts with carbonates, it forms calcium carbonate, a percipitate which cannot be used by coral. Coral must take in calcium and carbonates seperately and deposit them in their skeleton. Basically, the more magnesium you have, the less of a chance you have of calcium bonding with carbonates.

Low magnesium will stunt your coral growth, destabalize your alkalinity, and make it hard to maintain calcium and alkalinity. Magnesium is very often over looked, but is a very important part of the equation.

I purchase Magnesium chloride from

 

[derek_s]

Its complicated, and I'm not expert, but basically it is important to maintain the ionic balance of your tank. A good magnesium is especially important for SPS, but can also help maintain and regulate alk/ph/cA levels, and control algae (I've been told)

 

[derek_s]

They beat me to it, but right on. MArk, since you keep SPS, you probably should check it at least on occasion. THe good thing about mag is that once it is set, it usually stays consistent.

The test I use is the seachem one, but I'd say the elos one is the way to go.

 

[dannybradley]

A Mg shock to control hair algae is totally anecdotal. I've tried it several times, and only had it work once. We're talking 900ppm to 1400ppm in 30 minutes.

Which brings me to another note on magnesium. Try to only raise it by 100ppm per day. Although I've shocked with no ill results, more than that can be stressful to coral.

 

[derek_s]

Simon Kruger is the one that told me that, for what that is worth. I have no experience in the matter, but I can understand what you are saying.

It makes since that a shock would facilitate this.

What about growth? With the higher Mg levels reduce the algae proliferation? OR is the shock the real key?

 

[ralph atl]

here ya go:

http://reefkeeping.com/issues/2006-06/rhf/index.php">http://reefkeeping.com/issues/2006-06/rhf/index.php</a>


[IMG]http://www.advancedaquarist.com/issues/oct2003/chem.htm">http://www.advancedaquarist.com/issues/oct2003/chem.htm</a>


[IMG]http://www.reefkeeping.com/issues/2004-05/rhf/index.php">http://www.reefkeeping.com/issues/2004-05/rhf/index.php</a>

 

[derek_s]

I dont understand your last sentence, but I think it is possible to have good calc/alk with low mag. The key is that the mag will help stabilize this and avoid sways, or it dropping over time. THis is just and assumption, tho, and I'm sure Danny will know more specifically.

I would Def check your alk, as this is prob more important to regulate than calcium

 

[ralph atl]

ares;252541 wrote: long as this thread is here, which is really wierd since I was going to ask this question.

I just did a run of tests since starting aquavitro.

well my calcium is at 450, which is great I think, and higher than it ever was.

but my first mag test ever shows 930mg/l and they seem to suggest 1300-1400 as normal.

so I pulled out the magnesium aquavitro and it says add 7ml/35g to raise your mag 5mg/l? errr, I need to bring it up like 400mg/l. it also says not to add more than 7ml/35g per day. ok... so I should have it at 1300 in just about 3 months lol. what am I missing here? and how do I have fine calcium but low mag? should I be doing an alk test too to find out that its fubared by default for the other 2 to be where they are?

I would first, read those articles on those thinks I provided. That will help you immensely.

second, I would use a cheaper alternative on mag.

Get EVC or bulkreefsupply.com AND Epsom salts. 70%-30% mix is perfect. You can cheat a little and use more Epsom salt! LOL!

 

[ralph atl]

you can raise your mag 100ppm per day. go by calculator Charlie provided. it includes Epsom salt, too!

 

[ralph atl]

Magnesium is HARD to get it where you want, but easy to maintain as it doesn't deplete very much! Once you get there, you just check it monthly!

 

[ralph atl]

Elos!

 

[ralph atl]

ares;252566 wrote: well apparently my fresh mix salt water is not up to par on mag, so Id have to keep dosing with every water change.

Switch to SeaChem Reef Salt.
not scientific by any means

Calcium Alkalinity Magnesium

Aquatic Gardens
430 8 1240
CoraLife
560 9 1380
Crystal Sea Marinemix
340 9 1050
Crystal Sea Marinemix Bio-Assay
340 9 1050
Instant Ocean
350 12 1070
Kent
540 11 1200
Marine Environment
480 7.5 1450
Oceanic
580 8.5 1650
OceanPure
510 10 1320
Red Sea
400 8 1300
Red Sea Coral Pro
490 7 1300
Reef Crystals
420 12 1260
SeaChem Marine Salt
500 10 1400
SeaChem Reef Salt
540 10 1450
Tropic Marin
375 10 1230
Tropic Marin Pro Reef
450 8.5 1380
Tunze Reef Salt
420 9.5 1350

 

[ralph atl]

what mag test kit?

 

[ralph atl]

are you sure your salinity is at full strength? 35%? If you have a refractometer, is it calibrated to pinpoint calibration fluid or RO water?

 

[ralph atl]

Salifert should be ok, maybe off about 50-100 max.

 

[ralph atl]

How long have you been using Seachem? How big is your tank? How often & how much are your water changes?

 

[ralph atl]

Test kit: Did you follow the instructions STRICTLY? waiting periods, swirls, liquids dropped at 180 degrees?

 

[sailfish]

It could be a bad batch of salt. It has happened to me more than once with more than one brand of salt.

It always seems to take a crap load of stuff to raise your mag levels.

I also lost a purple pillow frag once from adding to much mag at one time.
I can always tell if I add to much because my Palmer's blue mille retracts it's polyps. Other people have mentioned this too. It's funny to hear of a coral acting the same way in different tanks and it's the only mille to do this. LOL

I like the elos test kit too. I once used a reference sample to test it's accuracy and it was right on.

Joe

 

[stacy22]

Echinoderms incorporate a lot of magnesium in their skeletons (in place of calcium). Their calcite has around 15% substitution of Mg for Ca. If you have a lot of echinoderms they will use some Mg. Also, chlorophytes (green algae) use Mg in their chlorophyll. Having said that, this use of Mg in no way compares to the large amount of calcium taken in by corals and other inverts.