I don't have progression pics so I guess you will need to just believe me... I have had 3 AI sol blue pods over a 130g for the better part of 2 years (as long as the tank has been running). On 2 other tanks prior I had MH. 250W for the same depth tanks. I think comparisons are difficult over time because so many people experience chemical swings over time, myself included, that may have more to do with growth or lack there of than the lighting differences between MH and LED. The other growth factor is flow and nutrient loads, EVERYONE has differences here which affect growth so this also makes it tough to judge. Having said that, I have had mixed experiences and I still like the LED.
My tank is SPS dominant. I have a small island with a few shrooms, 10-15 different types of zoas and paly's, acans, in addition to a blue stag, sunsest monti, candelight acro, and 2 unknown acro frags. I also have a couple blastos and an orange plate coral. The plate and blastos are directly below the light on the sand bed, the softy island is not in direct lighting. The par readings fall in around 300-250 depending on the side of the island. The orange plate sees 320 ish. The plate gets more light than it needs, polypos extend at night and during actinic periods.
3 types of duncans on the sand bed 1/2 in the light, 1/2 shaded and a large frog spawn hosting 2 clwns on the sand out of direct light. a Kryptonite candy cane on the sand bed that gets moderate light and grows like a weed. All the softies do well in my tank under LED's. The only deaths I've had in 2 years were Japanese blue cloves (more likely alkalinity related), Liam's cloves, and ATL tripple red zoas. Other than that I seem to get decent growth, certainly no slower or faster than when I had tanks with MH and the same or similar softies and LPS.
I get par readings with the clubs meter (which was suspect for inaccuracy at the time) around 420 at the high end of my rocks under the lights (lights are 18" above the water, rocks are 6-10" below the surface). I keep several colonies (blue, teal, Mike Acardi's teal, jesus, blue tipped, green stags, birds of paradise, pink birdsnets, green birdsnest, blue tenius, pink and rainbow stylos, Green, purple, and rainbow pociliporas, purple, orange, red, and pale green w/ blue rim caps, Blue and red milis, Oregon and toxic green torts, hawkins, sunset, undata, confusa, superman, pawlenenses montis, orange, peach, german blue digis, green sarmentosa, setosa, purple and green slimers, tri color valida, one sold to me as an aquadelight frag but now that it has grown out I think it is actualy a stag similar to Greg Hiller's teal stag, and a couple other acros I don't remember).
Many of these I have never owned with MH, but I can tell you what I think their growth rates are relative to each other under LED's (you would also need to know the % settings and times) and you can draw your own conclusions. Others I have had in both MH and LEDs for over a years growth time.
I would make the same general statements as others, my corals seem healthy and I do not experience RTN, bleaching, color issues etc. that I can pinpoint to light related. I run a single MP40 and get a good amount of flow from my returns. I would say any issue I have had has been related to ALK and my lack of patience with my calc reactor (I want the ph to go from 7 to 6.5 NOW, so I frequently fog the tank).
Some SPS do well as fast growers as expected, others creep as expected. Some have defied their description and surprised me with speed, others with slowness. But in general, all have grown and seem healthy with good poly extension, color etc...
I have a BRS pink mille.. that thing should grow like a weed and gets blasted with light. It is a nice pink color, but no vertical growth at all in any of the milles in my tank. They all spread along the rock as if they are encrusting montis. I have 2 other blue milles that do the same. I just picked up another type of blue mille yesterday, we'll see if it does the same. I had seen similar comments in the SPS forum on RC where people stated they had decent growth in SPS but it was all encrusting, little verticle. I would say my experiences are similar.
The other trouble coral has been Tri Colors. Validas just don't seem to like my tank. I have had 2 of them. To be fair, neither has been in direct light and they are high light corals. They looked good for a while but both have eventually developed RTN. I still can't pinpoint light as the cause though, the first was shortly after an alk episode.
Slimers - for get it. No matter where I put them, they encrust then stop. Zero growth in 2 years.
Birds of paradise, green sarmentosa, orange digi grow like weeds.
Pink birdsnest under a 250 MH I swear I could watch it grow... under LED's it is very slow, for a birdsnest anyway.
I have a RBTA that has decided to become a Red long tentacle instead... it climbed to the top of the rock and loves the light. I had a GBTA that tried to do the same, it sat side by side with the red for months and then dissolved last year some time. The red has looked great for 2 years. I do not feed it, and it does not seem to grow much nor move which is just fine by me.
Looking back I am happy with the benefits of LEDS over the last 2 years. My corals grow and have good color, maybe not as fast as they did under MH but I and my dogs certainly appreciate the lack of heat from MH lighting. In a small house, small room the heat was significant. I also appreciate the limited wiring and sleek appearance of LED fixtures. Aesthetics was important to me given this tank is part of my living room. The electrical savings were not as important to me, but I do appreciate not having to run the AC as hard.
