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sharko88
10/02/2017, 10:20 PM
So I just got my ICP-Analysis done on my tank. My corals have not been healthy for a long time even though I have added a doser (about a year ago) and an auto top off (2 years ago) to keep my Alk, Calcium, Magnesium level. I have Radion Gen 2's (non pro) and have long suspected the lights are the issue sine my parameters have been great. This was my last attempt to figure it out before buying new lights. I never had any issues with MH or T5's in other tanks and I have tried all sorts of intensities based on others suggestions with the Radions (letting 2 - 4 months between intensity changes).

Please take a look at my results and see if you see anything that would cause corals to have stunted growth and lousy color. From how I read this, my in depth analysis looks good.

bertoni
10/02/2017, 10:42 PM
The potassium level is about 100 ppm lower than the standard ocean level. Some people seem to find a correlation between a lower potassium level and coral problems. I'm not sure we have all that much high-quality data on the subject, but I would consider getting a potassium test kit and a supplement.

You might want to consider other issues, like possible copper contamination. The ICP analyses we get at hobbyist prices can be very inaccurate for trace elements, so I'd be cautious about trusting them too much.

sharko88
10/03/2017, 12:04 AM
Well one variable there is that I have not had any unusual invertebrate casualties. Correct me if I am wrong, but invertebrates usually have a high mortality rate in a tank with copper in it. I could be mistaken on that though.

orcafood
10/03/2017, 06:51 AM
shrimp bind o2 in their circulatory system with a copper based protein. So yes invert casualties would be a plenty if the levels were high enough.

dkeller_nc
10/03/2017, 08:34 AM
You do not appear to have any metals in your water that would lead to coral (or other invertebrate) poisoning. There is a caveat here; to truly do a complete profile of a water sample, it is necessary to acidify it with nitric acid when the sample is taken. Triton's kit doesn't include this because of shipping regulations and a potential hazard to the aquarist.

The reason for acidifying a sample is to immediately halt potential precipitation reactions that can occur in alkaline samples, and samples with high concentrations of precipitating counter-ions like sulfate.

However, if you truly had something toxic in your water, such as from a corroding piece of aluminum, I would still expect an elevated level in the Triton test.

I think your supposition about lighting is probably correct. It took several generations of product for LED aquarium lighting manufacturers to realize that light with a wavelength below 460nm was critical to certain coral species' health. This is particularly true for acropora species, though it appears to be less true for certain LPS and soft corals. Nevertheless, IMHO it is not simply inability to program a correct intensity and the point-source nature of LED lighting that caused issues in previous generations of LEDs. I suspect this is partly the reason for the resurgent popularity of T5HO/LED hybrid fixtures, and the considerably greater near-UV output of the 4th generation of Radions.

bertoni
10/03/2017, 04:36 PM
I agree that invertebrates are generally very intolerant of copper, so copper probably is not the issue. Changing the lighting might be an interesting experiment.

Alfrareef
10/04/2017, 01:59 AM
Following

dz6t
10/04/2017, 01:35 PM
I will say get a potassium test kit and retest potassium to confirm that it is really low.


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dz6t
10/04/2017, 01:36 PM
I agree that the light can be an issue. I have experienced washed out color for SPS under early generation of Radion.


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orcafood
10/04/2017, 02:59 PM
I had amazing growth with a diy led setup including the following:

405 nm
415 nm
448 nm
458 nm
528 nm
660 nm
6000K white led

I mostly copied the spectrum of the hydra 26 but changed a few diodes to match the action spectrum better. Sps were growing a half inch a month at least.

sharko88
10/08/2017, 12:58 AM
I will say get a potassium test kit and retest potassium to confirm that it is really low.


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I ordered one today. Would those low numbers discourage growth or just cause muted colors? Never doser or tested for potassium before. Is it usually in the salt mix? I use Reef Crystals.


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dz6t
10/08/2017, 05:23 AM
In natural seawater, Potassium is at 400 ppm. Most popular salt mix has the similar amount of potassium in it. Potassium does get consumed by coral and algae, but regular water change can replenish it.
Low potassium level can discourage growth theoretically but not a lot is known about by how much.
ICP-OES does have difficulty in reporting the right level of potassium in saltwater samples due to the interference of other major elements presented. It is a known issue and calibration is needed.


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orcafood
10/09/2017, 02:49 PM
Maybe some additional UV would help, the G2 only has blues and royal blues.

sharko88
10/09/2017, 02:53 PM
Maybe some additional UV would help, the G2 only has blues and royal blues.



Yep. Hoping that makes the difference. Really want only one type of light if I can and the area above the tank is enclosed so LEDs are the best solution for heat and air movement.


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orcafood
10/09/2017, 03:00 PM
Another thing is that I had my corals withing 4 inches of the water surface and 160 watts of led blasting barely 2 inches off of the surface of a 60 cube. Led penetration isn't that great without proper optics or tons of leds. I had no lenses on my leds but I was certainly not dialing back the light intensity for the sps once they were really growing fast.

dz6t
10/09/2017, 06:44 PM
Can you upgrade the G2 to G3 pro?


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sharko88
10/11/2017, 11:33 AM
Yes I believe you can but I won't be doing that as I want the optics and spectrum of the new G4s. Actually also going down to 2 XR15's at the recommendation of my LFS which is fine since I can't go above 50% on my current XR30's without coral starting to bleach which is nuts considering it is a 110 High. But I am also predominantly LPS with little SPS and some softies as well.

Yellow_donkey
10/12/2017, 01:15 PM
You should get a ICP-OES kit next time, more results including the base results reef tanks are concerned with.

bertoni
10/12/2017, 02:34 PM
ICP-OIS tends to be fairly inaccurate unless run very carefully, and careful testing is expensive. Tests run for hobbyists have been shown to have problems with trace elements, for example. I'd be cautious about trusting the results.

sharko88
10/12/2017, 09:01 PM
ICP-OIS tends to be fairly inaccurate unless run very carefully, and careful testing is expensive. Tests run for hobbyists have been shown to have problems with trace elements, for example. I'd be cautious about trusting the results.

I will say that I have confirmed some of the low numbers on the ICP-Analysis. The salinity was correct and the potassium seems correct based on the Salifert test kit I got. The salinity was verified with my refractometer after getting some 35ppm calibration solution. Ordered new lights though still as I think the XR15W Gen 4's will put out better spectrum than my Gen 2 (non pros - so no UV).

bertoni
10/12/2017, 09:19 PM
The issues with ICP seem to be more of an issue with trace elements, particularly metals. The potassium numbers might be more reliable, as I implied to at least some degree in my first post.

dz6t
10/25/2017, 08:50 AM
The issues with ICP seem to be more of an issue with trace elements, particularly metals. The potassium numbers might be more reliable, as I implied to at least some degree in my first post.



Regarding ICP for trace elements, that is ironic isnít it.



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