Instant ocean salt parameter

[hondas3000]

Hi everyone, I am new to reef and trying to have my tank stable and enjoy my tank but I have some question hoping for answer.

I am using instant ocean mix salt and I did a test from a fresh mix that power head and heated over night with gravity 1.025 and using the test kit salifert and this is what i get from the fresh mix

Alkalinity 3.7meq/l
calcium 400 ppm
magnesium 1170ppm

I did 10% weekly water change and here is my question with instant ocean salt is it a good parameter to keep coral? it is a mix reef so a bit of everything. Should i dose magnesium to 1200ppm to 1400ppm range?

My tank parameter right now is
alkalinity 4.22 meq/l
calcium 370ppm
magnesium 1170ppm

so should I dose calcium to bring it up to 400ppm and dose magnesium up to 1200-1400ppm range as well? and let alkalinity drop slowly to range? If I dose calcium how fast can I dose it? and what product should I use? can I use two part A and B or just calcium liquid itself. So please let me know what I should do and what I should continue doing so I don't end up killing any of my coral. Right now I just notice my majestic angel eating my zoas :(.

[Bblinks]

Yes I would dose mag first to raise it to the proper level, alk will slowly go down by itself and dose calcium once mag is at 1350 to 1400. Remember slow and steady, no more than 50 ppm per day.

Sorry to hear the angel is making a quick meal out of zoas. Time to start keeping some sps.

[Aquattro]

IO is lower in Ca, higher in alk. I would dose Ca in your new water and then maintain it with your chosen method between water changes. The alk numbers are fine, IMO.
Mg, I usually don't care about. I add some now to my new water, but see no difference vs when I didn't do anything with it. I'm still not sold on the whole Mg thing..

[hondas3000]

Yes I would dose mag first to raise it to the proper level, alk will slowly go down by itself and dose calcium once mag is at 1350 to 1400. Remember slow and steady, no more than 50 ppm per day.

Sorry to hear the angel is making a quick meal out of zoas. Time to start keeping some sps.


thanks that is what I am looking for as I don't know how much to dose in one day. Now I can dose it properly. THanks

yeah that angel is quick, and I also learn never place any zoas in an open area. 20pp in one bite :(

[hondas3000]

IO is lower in Ca, higher in alk. I would dose Ca in your new water and then maintain it with your chosen method between water changes. The alk numbers are fine, IMO.
Mg, I usually don't care about. I add some now to my new water, but see no difference vs when I didn't do anything with it. I'm still not sold on the whole Mg thing..


Thanks, Let just keep it by the book. Going to buy some bulk calcium now.

[mikellini]

I'd say it's worth raising mag to at least 1250ppm. Here's a snippet from Randy H-F's article on optimal parameters, regarding magnesium:

"Magnesium

Magnesium's primary importance is its interaction with the calcium and alkalinity balance in reef aquaria. Seawater and reef aquarium water are always supersaturated with calcium carbonate. That is, the solution's calcium and carbonate levels exceed the amount that the water can hold at equilibrium. How can that be? Magnesium is a big part of the answer. Whenever calcium carbonate begins to precipitate, magnesium binds to the growing surface of the calcium carbonate crystals. The magnesium effectively clogs the growing crystal surface so that they no longer look like calcium carbonate, making it unable to attract more calcium and carbonate, so the precipitation stops. Without the magnesium, the abiotic (nonbiological) precipitation of calcium carbonate would likely increase enough to prohibit the maintenance of calcium and alkalinity at natural levels.

For this reason, I suggest targeting the natural seawater concentration of magnesium: ~1285 ppm. For practical purposes, 1250-1350 ppm is fine, and levels slightly outside that range (1250-1400 ppm) are also likely acceptable. Higher levels may be fine, but there is no reason to keep it higher, with the possible exception of trying to kill bryopsis with certain magnesium supplements (which may work due to an impurity rather than the magnesium itself). I would not suggest raising magnesium by more than 100 ppm per day under normal conditions, in case the magnesium supplement contains any toxic impurities. If you need to raise it by several hundred ppm, spreading the addition over several days will allow you to more accurately reach the target concentration, and might possibly allow the aquarium to handle any impurities that the supplement contains (such as ammonia or trace metals).

An aquarium's corals and coralline algae can deplete magnesium by incorporating it into their growing calcium carbonate skeletons. Many methods of supplementing calcium and alkalinity may not deliver enough magnesium to maintain it at a normal level. Settled limewater (kalkwasser), for example, is quite deficient in magnesium relative to a coral skeleton. Consequently, magnesium should be measured occasionally, particularly if the aquarium's calcium and alkalinity levels seem difficult to maintain. Aquaria with excessive abiotic precipitation of calcium carbonate on objects such as heaters and pumps might suffer from low magnesium levels (along with high pH, calcium, and alkalinity). In general, magnesium is usually depleted at roughly 10% of the rate of calcium depletion, or less, depending on the creatures in the aquarium. Any depletion rate that is much higher than that is either due to testing errors, or water changes with a mix that has a different magnesium level than the aquarium.

Many people never need any magnesium supplements. Some salt mixes start so high that it will never drop below natural levels, and some calcium and alkalinity supplement methods, such as a good quality two part system, add enough magnesium that it should not decline."

[Aquattro]

You know what I don't understand? How people had successful reef tanks 8 years ago when Mg didn't exist in the hobby...it's weird.

[mikellini]

You know what I don't understand? How people had successful reef tanks 8 years ago when Mg didn't exist in the hobby...it's weird.

I don't understand how people had successful reef tanks in the 90's... but they did. Not sure what that has to do with magnesium.

The point of raising magnesium to close to natural sea water levels is to limit the abiotic precipitation of calcium carbonate. You can leave it lower, but you'll have to add much more calcium and carbonates to maintain a given level. Particularly if you're trying to maintain a level of calcium or alkalinity that's higher than natural sea water levels.

[Aquattro]

Not sure what that has to do with magnesium.



Sorry, I thought it was obvious. The point is, that until recently, Mg was not a factor. You couldn't buy it, there were no test kits for it. But we all had nice tanks and no problems keeping Ca and alk levels constant. We didn't have abiotic build up of anything, just SPS that grew fine. Just like now.

Jump forward to today, I see no difference in my tank with Mg @ 1250ppm vs last year when it was 1050ppm.

So, not saying it's good or bad, just saying that it might be over-rated.

[daplatapus]

This kinda gets away from the OP's original ? and into a Mg chemistry deal, but anyway...
All I have is my own personal experience, absolutely no real knowledge of the real facts or science behind it :)
I fought for over a year to get any kind of SPS growth, or really any growth to happen in my tank. I struggled to keep the big 3 parameters anywhere near optimal, usually one was always way out of whack. Then I read Sk8ters thread on RC and figured it couldn't hurt to scrap everything I'd been doing. I stopped dosing everything. I looked up BRS's dosing calculator and brought my Mg to 1400 over the period of a couple days. Then did nothing for a week but watch how that number fell and figured out my daily consumption. Dosed the tank again to get it back to 1400 and dialled in my 1.1ml doser and watched it for another week. Mg stayed rock solid. Then I did the exact same procedure for my Ca. After that I found my alk just dropped in line and followed everything except for just a minor dosing daily dosing to keep it topped up.
I've since moved to a Calcium reactor and have stopped dosing alk altogether. Been almost 2 years now and my numbers don't fluctuate at all.
I do top up my Ca in my water change water before I do it.
I fought and fought and fought to get good growth in my tank, but in my experience, it was only once my Mg was up, was I able to get any sort of stability in my tank.

[Aquattro]

I fought and fought and fought to get good growth in my tank, but in my experience, it was only once my Mg was up, was I able to get any sort of stability in my tank.

Dom, I hear that all the time, which is what makes me wonder why. I never dosed Mg (because there was none) and never had a problem. It's just one of those things that confuses me. I tried to believe, and added Mg, no difference in my tank. But really, for the cost of Mg, I don't see anything wrong with "just in case" application :)

P.S. Figured the OP got his answer already :)

[mikellini]

Dom, I hear that all the time, which is what makes me wonder why. I never dosed Mg (because there was none) and never had a problem. It's just one of those things that confuses me. I tried to believe, and added Mg, no difference in my tank. But really, for the cost of Mg, I don't see anything wrong with "just in case" application :)

P.S. Figured the OP got his answer already :)

Brad, did you notice any difference in the amount of calcium and alkalinity you had to add after raising magnesium? What do you run them at?

Again, it's not necessarily that it's a problem to have your mag a little low, just that it can be a little harder to maintain levels of other elements. Whether or not this has a noticeable effect in your tank will depend on a variety of other factors... I'm sure many people won't notice a difference.

[Aquattro]

my numbers have always been around 420/8dKh. This is with reactor or with kalk. Since I've never used a doser, I cant say that I used 4ml extra Ca with/without. But again, if I did, do I want to save 4ml Ca by using 20ml Mg (numbers made up, no idea what people use).

I can't/won't offer an opinion saying you need or don't, I just find it odd that so many tanks did so well for all the years before Mg came along. Maybe more do better now? I was kind of disappointed that after starting to use it, I didn't see any change in anything. I guess I was hoping for magical growth or something. But for the cost of the ice melt I'm using, I figure I'll just keep adding, mostly because Randy knows more chem than I do :)

[daplatapus]

Ya see, I couldn't get my Ca above 380ish until I boosted my Mg

[gregzz4]

Welcome to the dark side David :smile:

I would suggest the same as Bblinks did. Having your mag in that range makes it much easier to balance the other 2 while using less. Lower mag levels will give you a seesaw effect when adding the other 2 making stability difficult.

Many of us use IO Sea Salt. It's pretty normal for it to be high Alk, slightly low Ca and lowish Mag.

I dose mag and then ca to my new water before adding it to my tank. Some dose it after adding, and some don't bother at all. So it's up to you where you want your tank parameters to be.

As for what products to use there's the expensive, easy to use liquids and there's the inexpensive powders. Any one you choose is fine.
For now I'm using bulk powders and following Randy's 2-part. If I had the money I'd get a Calcium Reactor and dose mag accordingly.

If you haven't moved in the last 3 years you should walk over sometime for a chat and check out my system

[hondas3000]

Thanks everyone for getting into the topic. Like many mention here Mg need to be in check before adding cal or alk as I also notice I add lots of A and B dose and calcium liquid as well but still couldn't get Cal to increase pass 370 from 340ppm. Alk in other hand I see it increase so let me get Mg in range and dose cal after see if I can bring it up to 420ppm.

[hondas3000]

Welcome to the dark side David :smile:

I would suggest the same as Bblinks did. Having your mag in that range makes it much easier to balance the other 2 while using less. Lower mag levels will give you a seesaw effect when adding the other 2 making stability difficult.

Many of us use IO Sea Salt. It's pretty normal for it to be high Alk, slightly low Ca and lowish Mag.

I dose mag and then ca to my new water before adding it to my tank. Some dose it after adding, and some don't bother at all. So it's up to you where you want your tank parameters to be.

As for what products to use there's the expensive, easy to use liquids and there's the inexpensive powders. Any one you choose is fine.
For now I'm using bulk powders and following Randy's 2-part. If I had the money I'd get a Calcium Reactor and dose mag accordingly.

If you haven't moved in the last 3 years you should walk over sometime for a chat and check out my system

Hi Greg, good to see you here as well. No I haven't move anywhere yet just more busy with life only. I am still in debate of getting a doser or the calcium reactor for my 180G. I have no problem dosing it just need to get something that cost effective and easy to maintains and more time to enjoy the tank. Don't want to turn it into a part time job just to keep up with the tank. Maybe my next topic would be reactor or doser for 180G tank?

[gregzz4]

I think you just answered the debate
A reactor is much less work as far as I understand

[daplatapus]

No question in my mind. For a 180 with any amount of SPS, Ca reactor is the way to go. I regret I didn't do it sooner.

[mark]

typical ocean water (http://reefkeeping.com/issues/2004-05/rhf/) is Ca-420, Alk-7 and Mg only 1280, personal experience easier to bring the Ca up if Mg isn't low.

[LeanneP]

I have kind of a dumb question, but if you have a calcium reactor, do you not have to dose alk? I have a doser and my sps are growing like crazy. It's getting a little expensive for chemicals.

[daplatapus]

Nope, no dosing alk for me. The dissolution of the aragonite media boosts both the Ca and alk.

[Aquattro]

Nope, no dosing alk for me. The dissolution of the aragonite media boosts both the Ca and alk.

zactly!

[LeanneP]

Good to know. Not sure how I missed that along the way. Never stop learning in this hobby.