mag i got from dsas

after hearing u guy say it is really hard to over dose on mag i wanted to dose my tanks. its 2 little fishes. it recomends 1 cap fo every 10 gallons. i would pro use 1 cap every week. i dont have a test kit right now. i will be getting one soon hopefully. should i weight or go for it??? thanks.

i also have iron. anyone test for that??? what are benifits of using it and would u recomend me(no test kit) to use it. brett



Fe(iron) is very controversial. Personally, i dont feel it has a place as a dosed supplement in a reeftank. The trace amounts you get with waterchanges should be more than enough. Save you Fe for your planted FW tanks.

1 cap= +5

I’m from the school of thought “If you don’t test for it don’t dose it”. If you do use the mag. I don’t think I would do a full dose anyway. If you do regular water changes you mag should be about right; this would be a supplement to the existing mag.

Iron is really only needed in fully planted marine or freshwater tanks in my opinion. In keleigh’s 15g Iron isnt the limiting factor for plant growth, phosphates and nitrates are. Unless you have a refugium that has macro in it that is not growing, but Nitrates and Phosphates are both present, I would say stay away from the Iron supplement.

For the Magnesium, I would say that as long as you keep it below the recommended level you shouldnt hurt to much. Some may disagree, and I agree that waterchanges should supply most of your nutrients, but from what I have read a high magnesium doesnt really hurt to much, other than possibly some forms of hair algae. Again, it is probably better to test for it, but you probably wont kill anything by adding it as long as you arent big into the SPS. With that said, it may also not really help anything either… there is no telling.

al thats what i thougth. but after the meeting i figured i mid as well ask. i top off every day and do water changes as needed (between 1-2 week). whats a mag test kit run ya???

I would keep Mg within the ranges. IMO buying a Mg test kit is worth it if you are going to be dosing it and especially if you have SPS or coraline algea on your LR- I have noted some SPS bleaching at times when I accidentally dosed over 1350ppm. if you dont have either youre probably OK with your h2o changes there

I wouldnt bother dosing Fe unless you have a refugium. if you do, I say go for it. I have dosed it myself quite often and noticed increased cheto growth. Fe is one of the few trace supplements that I have seen actual results from in my macro algeas and I will dose it again in the future. I dosed a cap full twice a week or so. realize though that it will also help nusance algeas… I have never tested for this one as I have not correlated any negative affects to my SPS with its dosing.

I Know inverts need iron also but if you do regular water changes that should be enough

(1) Wait wait wait wait wait wait wait till you get a test kit
(2) Test what you have
(3) Then determine if you need to dose.
(4) Repeat test after you dose to get a feel for what you just did.
(5) Repeat steps 2 - 5 as needed.

Agree with Al, if you don’t test for it, don’t dose it. That’s the rule of thumb I always follow. When I first started with corals I overdosed Ca and whipped out an awsome clean up crew. Then I bought a test kit which didn’t have clear directions I thought I was still way low so I kept dosing more and more and kept getting lower and lower measurments.

Test for Calc, Alk, and Mg and make sure the results make sense to you and test accordingly. If you start adding one, but not the others it can possibly hurt things more then not dosing at all.


what salt do you use? some salts are low in Mg, and Ca and alk, while IO is pretty good. i use a low cost salt that is low, but just supplement it with Mg Ca and alk as needed. per the calculator on Reef Central after running some tests.

it takes a whole lot of Magnesium salts to raise the MG level very much. mostly because the magnesium salt compounds conatin a small percent of Mg by weight. mostly other elements in the salts.