chadfarmer
Premium Member
just becuase they come from a 400 watt mh doesnt mean that the light is brighter than your setup
Interesting debate going on. It would seem to me that there is a bit of semantics here. One side saying nutrients are high but appear low due to rate of absorption or cycling and another saying nutrients are low.
From my studying and knowledge your both right to some extent. Ultimately scientist will tell you that the nutrients on a coral reef are low relative to surrounding water. But that doesn't mean there aren't significant amounts of organic matter, trace elements, and microscopic fauna.
When hobbyist talk of ULNS the idea is to avoid the historical problem of systems building up nitrates, turpenoids, tannins, phosphates and other contaminants. It doesn't necessarily mean that we want the tank free of foods, plankton or other nutrients needed by corals. In fact, the trick is trying to get the nutrients in but to export them before they build up enough to convert to the toxins described above.
For the record my tricolor also bleached, continues to grow at the base but remains discolored. Came from a MH system and is now in a DIY LED lit tank. Unfortunately, I think the initial bleaching came from too much light. I ran the RB at 100%. Other SPS at mid level began bleaching while those lower either did not bleach or bleached less including frags of the same colony. I have since cut the lighting in half and seen some improvement in most corals. The valida is perhaps the least improved, yet still growing.
It may in fact be a combination of factors, not just one. My nitrates and phosphates are zero also. IMHO if I had not bleached the valida with too much light in the beginning, I think it would be much better pigmented today. I think they are just slow to regain their pigments.
I have seen valida look good under t5, LED, and MH. I think we need to be more careful acclimating corals to the light. Without PAR meters it is very hard to tell how much light we are providing. I believe it is much easier to color up a browned out SPS from low light than a bleached out from excess light.
For now I will keep my valida in a lower light, keep Ca, Alk mg in ideal range. Allow nitrates to go up as high as 5 if they trend that way and still keep phosphates as low as possible. I am trying to add aminos and trace elements along with occasional coral feeds. Let's keep sharing our experiences so maybe we will figure this mystery out!
Thanks folks. I'll tag along.
I, like everyone, would love to get to the bottom of this. It definitely seems that it is a common problem with valida, although not exclusively.
I don't believe flow is an issue. Yes, it is random, but it is also very powerful. In my 75g, I have a Koralia 4, a Koralia Magnum 7, and a Tunze 6065.
I am ramping up feeding. I think my skimmer will remove the majority of the excess. I also think I probably light-bleached the coral initially.
Thanks again for everyones input. I am learning a lot!
Dzhuo I agree with you a 100%
I forgot to mention that I have a Fiji tricolor valida from bluezoo.
It sits 6 inches from an AI sol white sitting on a plexiglass cover turned up to 50% on white. I thought it was getting blasted with light...
It's a nice sized colony about 4+ inches across. It actually grows quickly and TOWARD the light. The side that is closest to the slightly offset AI sol has active growth and nice purple extensions. The rest looks "bleached" like yours but I think the purple is most evident when the coral is actively growing (as was mentioned).
I forgot to mention that I have a Fiji tricolor valida from bluezoo.
It sits 6 inches from an AI sol white sitting on a plexiglass cover turned up to 50% on white. I thought it was getting blasted with light...
It's a nice sized colony about 4+ inches across. It actually grows quickly and TOWARD the light. The side that is closest to the slightly offset AI sol has active growth and nice purple extensions. The rest looks "bleached" like yours but I think the purple is most evident when the coral is actively growing (as was mentioned).
The side that is growing is also closest to the MP40 as well.
I have been dealing with other issues so I have not addressed this growth imbalance yet, but this AM, I turned the AI sol lengthwise directly over the valida and I'll see what happens.
If it isn't flow, I'll bet that the growth has slowed down and the coral has thus lost the purple tips. Once you figure what makes this coral grow, I have a feeling the purple tips will come back. More feeding and more light would be my next try.
I can post a pic of mine if it would help.
iwishtofish, how old is this reef tank? Is it well established? I didn't see this mentioned earlier in this thread. I too am surprised by how "clean" (re devoid of life the rocks look). It really looks like low nutrients to me.
Myself as well...
Show me someone with an actual ocean in a box and then we can talk about natural settings.
We may need to look up the p04 and n03 numbers from the ocean and talk about how we as hobbiest try to achieve those numbers. I'm not sure I would call it irresponsible either but that's my opinion as well. Again ULNS is thrown around loosely with SPS.
It's been suggested to me in the past that my tank might be too clean, but I am afraid to put too much food in there because I don't have any livestock other than snails and a coral banded shrimp. I am imagining a sudden algae outbreak. I do have a skimmer way over-rated for the tank, though (Reef Octopus rated for 200g).
I have a 40g with a skimmer rated at 200g so i doubt the skimmer is any issue.
All I have tested recently are alk (8 dKH), and Ca (400ppm). I tested Mag not too long ago and it was around 1250.
I am using mostly ATI bulbs, now 7 months old. A combination of Blue+, AquaBlue, Fiji Purple, and GE daylight, I believe. The fixture has been around 8" over the tank, and the coral is mid-level in the tank. I did just raise the fixture a bit.
My bet is you bleached it and your light is putting out crazy par so its staying bleached. Have you thought about getting a par meter?
Dave, thanks so much for your reply! Your tank configuration seems very similar to mine, at least with regard to filtration, and your coral had neary identical coloration to mine when I first got it.
I did not acclimate the coral properly to my lighting. My error in judgment arose as a result of my belief that the store tank had much higher par than my tank. Lesson learned!
Would you recommend that I just raise my lights and see what happens? I'm currently planning the introduction of a Kole tang.
I did not acclimate the coral properly to my lighting. My error in judgment arose as a result of my belief that the store tank had much higher par than my tank. Lesson learned!