Strontium and the reef tank

[Squamosa]

Hi all and specifically Randy Holmes-Farley

I would like to share my experiences with dosing strontium and the results in an anecdotal way!

I recently decided to switch my tank to the Dutch Synthetic Reef (DSR) system of reef keeping and after testing for many different parameters came to some interesting conclusions. My system is relatively small at 500L and stocked with primarily SPS corals, some chalice and Acanthastrea sp.

Strontium dosing to maintain levels as close to or slightly exceeding NSW (10 ppm) was my goal initially.

I used the Salifert Sr test initially to check existing levels and found my water to be so depleted in Sr that a reading did not register at first. This despite the weekly, 20% addition of artificial salt water for water changes using the regular Red Sea salt. I have in the past, but not for the last 6 months, used the Red Sea calcium supplement for 2-part dosing, I believe this has some Sr added to it. For the last six months I have been dosing your recipe, part 1, for all my NaHCO3, Ca and Mg needs.

Bicarbonate, calcium and magnesium have always been kept at, ~7.5 dKH, ~410 ppm and ~1300 ppm, respectively. My lighting schedule (Radion LED's), temperature (25 degrees C), salinity (1.025 sg) and water flow have not changed and I don't feed the corals anything.

I started dosing strontium chloride at 1 ppm/day and after ten days (testing every day) had my first reading at 1 ppm. some people in Europe I consulted, said that a 'buffer' needed to be built up first as all my available Sr had been used up. Finally after 20 days my Sr level stabilised at 10 ppm and has remained at this level with daily dosing of 0.05 ppm/day.

The SPS corals, especially the Acropora sp. have reacted remarkably, in the following ways:

• Side branching especially in A.spathulata, A. millepora and 'staghorn' types!
• Increased growth in all acropora sp. (growth tips).
• Increased basal encrustation.
• Thicker growth (sturdier branches) in 'staghorn' acropora sp.

There has been no noticeable change in colour.
Acanthastrea sp. look the same as do all 'mushroom' corals and chalice.
The change has really been very surprising and welcome.

On a side note, I have also tested for boron and this value is extremely high at ~ 15 ppm, despite never having been added to my system except through water changes and as someone suggested to me, through the food I feed my fish! But that is a discussion for another day

What has been your experience, if any, with strontium dosing?
Here is a picture of a happy Acropora :wink:

Cheers,
Tony

 

[tyler1503]

Interesting
I've always liked reading the chemistry related posts about the trace elements we generally ignore.

 

[naso tang]

Following along, I too dose both strontium and potassium on top of brs two part, although I've never tested for either in my sps dominant. I think it's essential but not sure I'm dosing enough. My growth is great but some colonies are more brittle than I'd like. I have a hard time gauging whether I have enough trace elements in the system in addition to these two elements when doing weekly 10% water changes. Don't want to overdue it but I don't have all the test kits I need to assess.

 

[kireek]

I have not dosed for Strontium.Your post has me convinced that I should start.I wonder why SPS does better in one of my tanks and am curious about the levels of the various trace elements.May I ask for details regarding the Salifert test kit procedure? Is fairly simple and/or time consuming?

 

[Squamosa]

Following along, I too dose both strontium and potassium on top of brs two part, although I've never tested for either in my sps dominant. I think it's essential but not sure I'm dosing enough. My growth is great but some colonies are more brittle than I'd like. I have a hard time gauging whether I have enough trace elements in the system in addition to these two elements when doing weekly 10% water changes. Don't want to overdue it but I don't have all the test kits I need to assess.

I dose K+ too!

I would recommend you test for any elements that you add, firstly to establish initial values and then to get a baseline for dosing

Salifert make a really good (not too complex) K+ test kit.

 

[Squamosa]

I have not dosed for Strontium.Your post has me convinced that I should start.I wonder why SPS does better in one of my tanks and am curious about the levels of the various trace elements.May I ask for details regarding the Salifert test kit procedure? Is fairly simple and/or time consuming?

For me, strontium has made a big difference regarding growth.

The Salifert test kit is a titration based test and is relatively easy to use. It just takes a little longer as you first test for calcium and then move onto the final step, this takes between 12-15 minutes. I have found the test to be relatively accurate, however, the down side is the cost per test as you only able to do ~25 tests per kit.

Remember, google is your friend :wink:

Cheers

 

[Randy Holmes-Farley]

Very interesting. What exactly did you dose? Brand?

I would say that this result is somewhat unusual as a lot of folks who previously dosed strontium noticed no change when they stopped doing so, and so then did not retain it as part of their regular routine. Because of that sort of experience, and very few clear cut cases where it was useful (coupled with the fact that strontium is not known to be needed by most organisms we keep), has led me to generally recommend that folks not bother measuring or supplementing it. I've personally not noticed any effect from strontium additions in my tank, but I do not keep much SPS.

Strontium looks very much like calcium, and it gets deposited into precipitating calcium carbonate in place of calcium. That is equally true wither it is a coral depositing its skeleton, or abiotic precipitation on heaters, pumps, etc. So strontium will decline in a reef tank if it is not supplemented somehow.

I think it would be a very interesting and useful experiment for folks to carefully test strontium dosing in their systems, while changing nothing else, and look for changes. In the past, and with comemrcial supplements, many people dose strontium in combination with other things, making it impossible to really know what has been useful in those additions, so if the purpose is an experiment, be sure to dose strontium chloride only.

 

[Randy Holmes-Farley]

Following along, I too dose both strontium and potassium on top of brs two part, although I've never tested for either in my sps dominant. I think it's essential but not sure I'm dosing enough. My growth is great but some colonies are more brittle than I'd like. I have a hard time gauging whether I have enough trace elements in the system in addition to these two elements when doing weekly 10% water changes. Don't want to overdue it but I don't have all the test kits I need to assess.

FWIW, I would not assume that potassium is being depleted. It isn't in my tank without any dosing. If you are dosing enough to make a difference, it might be getting too high, and if you are dosing only a little, it might not be enough to be useful if it is depleted.

Potassium consumption is not tied to calcification since it isn't significantly incorporated into skeletons, so gauging the need based on other supplements needed may not be optimal.

Potassium is taken up into cells, and growing cell/tissue mass will deplete potassium. OTOH, potassium comes in in the cells of all foods as well.

So on balance, whether there is any depletion of potassium will depend on the relative amount in the foods you feed relative to the tissue mass that those foods are being incorporated into (bacteria, macroalgae, corals, etc.).

 

[MattinIdaho]

Would it be possible to have too much strontium present? Enough to cause skeletons to become overly thick. My sps of any kind does not branch out. It simply encrusts or grows in a solid clump. Pieces I've had for over 3 years. Polyp extension is normal as well as colors. I've never tested for strontium but this is the only possible clue I've had to this issue. I don't know why it would be high. I use RSCP salt and dose only Ak (100 ml per day), and Mg (200 ml per week in a 180 gallon system. I just recently quit dosing lugals at a rate of 7 drops per week but had the issue before I began dosing that. Ideas?

 

[Randy Holmes-Farley]

Would it be possible to have too much strontium present? Enough to cause skeletons to become overly thick. My sps of any kind does not branch out. It simply encrusts or grows in a solid clump. Pieces I've had for over 3 years. Polyp extension is normal as well as colors. I've never tested for strontium but this is the only possible clue I've had to this issue. I don't know why it would be high. I use RSCP salt and dose only Ak (100 ml per day), and Mg (200 ml per week in a 180 gallon system. I just recently quit dosing lugals at a rate of 7 drops per week but had the issue before I began dosing that. Ideas?

If you don't dose strontium, it is very unlikely to be too high.

also do not know what happens when it is too high.

High flow makes SPS grow more thickly. Is your flow unusually high?

 

[naso tang]

FWIW, I would not assume that potassium is being depleted. It isn't in my tank without any dosing. If you are dosing enough to make a difference, it might be getting too high, and if you are dosing only a little, it might not be enough to be useful if it is depleted.

Potassium consumption is not tied to calcification since it isn't significantly incorporated into skeletons, so gauging the need based on other supplements needed may not be optimal.

Potassium is taken up into cells, and growing cell/tissue mass will deplete potassium. OTOH, potassium comes in in the cells of all foods as well.

So on balance, whether there is any depletion of potassium will depend on the relative amount in the foods you feed relative to the tissue mass that those foods are being incorporated into (bacteria, macroalgae, corals, etc.).

Never thought about it that way, thanks. For sps (particularly montiporas) I think it helps with color so it may be influencing the pigment production/ biology more than the calcium deposition. My tank sucks up a lot of ca++ that's for sure see for yourself

 

[-Logzor]

What products are you using for raise strontium? Or do you use the straight chemical from a lab supply store?

 

[Squamosa]

Very interesting. What exactly did you dose? Brand?

I would say that this result is somewhat unusual as a lot of folks who previously dosed strontium noticed no change when they stopped doing so, and so then did not retain it as part of their regular routine. Because of that sort of experience, and very few clear cut cases where it was useful (coupled with the fact that strontium is not known to be needed by most organisms we keep), has led me to generally recommend that folks not bother measuring or supplementing it. I've personally not noticed any effect from strontium additions in my tank, but I do not keep much SPS.

Strontium looks very much like calcium, and it gets deposited into precipitating calcium carbonate in place of calcium. That is equally true wither it is a coral depositing its skeleton, or abiotic precipitation on heaters, pumps, etc. So strontium will decline in a reef tank if it is not supplemented somehow.

I think it would be a very interesting and useful experiment for folks to carefully test strontium dosing in their systems, while changing nothing else, and look for changes. In the past, and with comemrcial supplements, many people dose strontium in combination with other things, making it impossible to really know what has been useful in those additions, so if the purpose is an experiment, be sure to dose strontium chloride only.

Hi Randy

To answer your question, I am a scientist and have access to laboratory grade strontium chloride which is then made up to a stock solution and dosed according to the volume of the tank, beginning with 1 ppm/day. Certainly no brands were added that contain strontium but also contain metals such as molybdenum!

I found that my system responded well to the addition of strontium! Whether or not it was mistaken for calcium by my sps corals and deposited is debatable as my calcium levels have never been on the low side, certainly never so low that strontium was being used as the main skeleton building element.

No other parameters were changed in my aquarium and no additional strontium was added in the form of water changes, as all water changes have ceased. You mention in your article from 2003 that Julian Sprung observed similar changes to his system, it's just a pity that he did not record the values present before and after in his aquarium.

Now that my strontium levels are where I want them to be, I have started with iodine supplementation and can see changes in colouration, some quite dramatic!
I certainly don't assert that anyone should dose strontium or any other element for that matter into their aquaria, for me it's a matter of having control over as much as possible and seeing the effects, it certainly is not a perfect experiment but I have documented the results

I see your presence on this reef forum has already added value and enlightenment to many discussions :wink:

Cheers,
Tony

 

[MattinIdaho]

If you don't dose strontium, it is very unlikely to be too high.

also do not know what happens when it is too high.

High flow makes SPS grow more thickly. Is your flow unusually high?

No not unusually high. Right now I have a mag 12 on one return and a 9.5 on the other. Powerheads are 2 Koralia 6's and 1 Koralia 5 on a smartwave in a 180 gallon dt. Doesn't matter where in my tank the coral is either. My Monti's are so thick they are unbreakable by hand and plate out very very slowly. This is something I have fought since I started the hobby. Very frustrating as sps can be kept but is not appealing to look at because it just encrusts and grows enormous bases without growing vertically. I raised the question of my problem in a thread entitled "begging for vertical growth help" that is a little more detailed. I was just hoping you had seen something like this. I have searched for years and not found a solution. It's gotten to the point that my only choice is to personally start dosing vodka in copious amounts.

 

[naso tang]

What products are you using for raise strontium? Or do you use the straight chemical from a lab supply store?

Personally I use brightwell strontium and potassium. Just a few drops of each per day. I really only do this cause my two part system does not add trace elements that are included in the commercial two part recipes such as bionic and two little fishes. I use brs and between my bioload and skimmer, I'm adding about 100 Mls ca and alk per day

 

[Randy Holmes-Farley]

To answer your question, I am a scientist and have access to laboratory grade strontium chloride which is then made up to a stock solution and dosed according to the volume of the tank, beginning with 1 ppm/day. Certainly no brands were added that contain strontium but also contain metals such as molybdenum!

I found that my system responded well to the addition of strontium! Whether or not it was mistaken for calcium by my sps corals and deposited is debatable as my calcium levels have never been on the low side, certainly never so low that strontium was being used as the main skeleton building element.

Thanks, Tony.

I wasn't suggesting that in your case that the corals were using it in any greater proportion than in NSW. I was just indicating how it is mostly consumed.

 

[reefwiser]

Tony, great read on how you are doing with DSR hope to have my tank started next month. It is nice to notice the changes based on dosing pure chemicals and recording the readings an getting the response you are seeing.

 

[Squamosa]

To answer your question, I am a scientist and have access to laboratory grade strontium chloride which is then made up to a stock solution and dosed according to the volume of the tank, beginning with 1 ppm/day. Certainly no brands were added that contain strontium but also contain metals such as molybdenum!

I found that my system responded well to the addition of strontium! Whether or not it was mistaken for calcium by my sps corals and deposited is debatable as my calcium levels have never been on the low side, certainly never so low that strontium was being used as the main skeleton building element.

Thanks, Tony.

I wasn't suggesting that in your case that the corals were using it in any greater proportion than in NSW. I was just indicating how it is mostly consumed.

Certainly no offense intended on my part :tongue:

Having a noted chemist such as yourself who has published widely and has such a passion for reefkeeping informing us here, is wonderful news!

As you rightly say, too many variables are being put into our reef tanks to definitively state that one element has made a difference, I am only adding pure substances to my system, one at a time, and documenting the results.

Perhaps a revision of your 2003 work on strontium is in order

Cheers,
Tony

 

[Squamosa]

Tony, great read on how you are doing with DSR hope to have my tank started next month. It is nice to notice the changes based on dosing pure chemicals and recording the readings an getting the response you are seeing.

Hi reefwiser

I was sceptical at first on switching to DSR, but the health of my reef inhabitants has not suffered, quite the opposite has occurred!

I am getting good results and could not be happier, GlennF does a great job at mentoring.

Keeping the individual elements at NSW levels or slightly elevated has made a world of difference to my reef.

Cheers,
Tony

 

[Squamosa]

Never thought about it that way, thanks. For sps (particularly montiporas) I think it helps with color so it may be influencing the pigment production/ biology more than the calcium deposition. My tank sucks up a lot of ca++ that's for sure see for yourself

A beautiful reef tank