Very Slow SPS Growth

I am concerned about the growth of two SPS frags I bought. I have had a Green Acropora Prostrata and a Pink Birdsnest (Seriatopora Tellata) for about eight months and have seen very little growth if any. For example, a tip from a branch from the Pink Birdsnest has grown only 1mm in this time frame. The Acropora Prostrata show no signs of growth. Both corals all show good signs of health ( extending polyps ect ). All my other mushrooms, polyps and LPS grow like crazy.

I'm not sure what could be wrong, but I have a couple ideas. My Alk is at 3.5meq/L, which seems low, and Calcium is at 420ppm which is good. I'm using Seachem Reef Builder, and Advantage Calcium. I've tried increasing dosage of the ALK supplement, but I'm above the max recommended amount and the ALK is not increasing. I have heard Seachem ALK & CAL suppelments are no good, so I'm looking at getting a hold of the E.S.V. B-Ionic 2-part setup. Other potential problems could be low nutrient and Iodide levels caused from over skimming, and maybe Strontium and Bromide levels which I have not tested. I also use Seachem's Reef Trace and Reef Plus, but I'm not sure if it's helping.

Does it sound like any of the above could be solutions?
What should I do or try?? Please help.. Thanks

 

Mission and Geekafied have the low downs on sps,
but sps grow slowly and require intense light and MOST sps don't like nitrates at all
seems like they should have shown more growth than that though.

 

You may be having a hard time raising your alk because your magnesium levels are low. Any idea what they're at?

 

My nitrates where at zero when I got them and have been there forever. They get good flow from the wavemaker ( I can see the Polyps sway back and forth). Light is good 14,000k 150MH with 32W actinic PC, and they are positioned close to center mid level. I haven't repostioned them because I don't much room in my nano.

Amcarrig, I forgot to mention, last time I checked MAG., about one month ago, it was 1280ppm.

Another thing I didn't mention, I feed and random variety of foods like Kent Phytoplanton, Micro-Vert, Chromaplex, Zooplankton, Spiralina, frozen Brine shrimp, Plankton, Daphnia, Mysis.

 

Pink birdsnest and acropora do tend to be slow growers, especially when compared to green birdsnests and montipora corals. I still think you should be seeing more growth though.

 

Well the reason the SPS seem to be growing slowly could be several reason But I'd look at the Nitrates first then that the Alkalinity level is a bit to low it is about 1/2 of where it should be. The Magnesium should be up nearer to 1400 to 1500 .

Forget about iodide or iodine levels and I'd not dose any of it either.. Strontium is a needed element but not that much for just two corals if you are doing any water changes the stront and iodide should be in the newer water , That being said iodine and strontium tend to get people in to trouble dosing it .. The Strontium is a funny element to deal with almost impossible to get a really accrurate test or reading of the amount in the system , Best leave strontium alone untill you gain the experience to deal with it..
As for paying attention to the labels dosing amounts Just put as much in as you need to raise the levels .. to get the levels up to where you want them bang it on up adding in a small tank like that about 2 tbls at a time mixed into some fresh make up water.. Same applies to the Mag and Ca.. Keeping them at proper levels will domore for growth then you think.. But again look out for nitrates with what all you are trying to feed the tanks that may become an issue.

But you get the Ca 450 to 500 the DKH to 12 to 13 and the Magnesium to 1400 to 1500 and get the water as clean and clears as possible they will grow.. Remember with any reef tank if its healthy and growing then what was enough to add last month will not be the same amount next month. And there is no way any label can tell you how much to add.. So use the test kits and kick the levels on up there. And keep them there with weekly testing and adding what ever as needed to maintain them .

 

Thanks Tangster, I'll try boosting my Alk to 5-6meq/L (14-16.8 DKH), like you said, and nudge my Mag. to 1400ppm.
My Nitrates are at zero, so that's not the problem.

How about my skimmer. I know this is a hot topic, but is it a good idea to run the skimmer 24/7. I feel like it is lowering my nutrient levels. Kind of a weird experience why I think this, but it is possible to overskim, right??

I was wondering if I should give the skimmer a break for some time and try not using it for a while, along with fixing my Alk and Mag...

 

A skimmer is just that , And there is more to it then just removing elements good or bad from the water. Honestly all I ever had one to pull was dye's in the additives most dose. Thats like with Iodine and any colored trace element its just the dye's And the other side of the coin is they do remove some elements of metals .
I had this discussion about 10 yrs ago when a famous Dr aquarium guy hit on all this skimmer is bad stuff , I told them all that would listen is yes they will pull some wanted elements but only to the point of them being in the system to excess. Then being who they are they all demanded Data.. I have no data I have a life. Well all was going along just swimmingly no pun and they all where just yakking it up ...
And at that time it was the skimmers that was killing and causing his Deep sand bed crashes so it was no skimmers They are bad and all jumped on the wagon for about a yr is all it took then they all started to fail again..Well what was found out to cause the problem was excess metals where being absorbed into all of their rocks and sand until they all just rolled out. And wiped out their tanks again then it was back to the skimmers as they are much needed and where not the DSB cause of failure's..

Not to mention the dissolved oxygen and higher ORP and or Redox that they add to the systems water quality.. I run mine 24/7 and I never wold cut it off intentionally. But you can have to large a skimmer for a system also..I know its confusing as hell and a difficult topic to deal with.. But Like I said I do not deal in Data , I have over time found that a properly sized skimmer for a reef system is simply a must for top quality water.

But they like anything can be over done and most times are . I have found that if I size my skimmers too match the flow rates through the sump more then how many will for the tanks size its a better deal all the way around.. And over skimming is never a issue . But I myself would never run a system with out a skimmer.. I base that on the many yrs I did not use skimmers and I remember those tanks )>: And not because I have not tried to recall them ..

And also remember all corals do not respond the same nor share the same growth rates Thats comes from generations of being tank kept I have a blue tort Acro and its been in my care for 18 yrs or so and it grows way faster now then it did when I first got hold of it and we had a frag of another one almost just like it , mine out grew that one at rate of 5 to 1 My frag I brought up here went from a twig to softball sized in 1.5 yrs te other got to about golf ball size , Never think they should all grow at the same rates, I haver a Green acro that will overgrow everything in site I snagged it from Fla. in the late 70's That went from twig frag to football size in a yr.