GP Diet (5-50 micron) Growth and BSD

[Logzor]

I plan on buying the 5-50 micron golden pearls from brine shrimp direct. I was given a small amount to try for a couple of weeks, I did nightly feedings of around 1/16 teaspoon, maybe more. I was very happy with the results, increased polyp extension from my sps, color seemed to improved but of course this could just as easily be coincidence.

I was originally tuned on to them after reading this article in AA.

http://www.advancedaquarist.com/2007/6/aafeature1

Even though the GP were not show to increase growth, I still believe they have potential. Number one, I believe they used a larger side, above 5-50 micron. Two, there was little if any flow in their test, it is no wonder the live food performed, they could swim!

Do you think that the GP have potential to perform as well as the live food?

Anyways, if the GP can perform like the live food or even half as well, we could see significant growth in our reef systems. The problem is that we do not know the effect of normal food (fish poop) compared to the GP or live food, since that was not part of the study.

Anyways, since I am going to make this order, dose anyone recommend other products from BSD?

[Amphiprion]

Just going from the results, I wouldn't. It is very evident that, at least in Pocillopora, that there is little interest in that food. Sure, it may elicit a response, as do your hands in the water (at least mine do), but the corals clearly don't seem to eat it at all. Seems like another way to increase nutrient concentrations or potentially feed other things. What those other things are, I don't know, but as far as corals go, I'd try something different. That's just me, though.

[Logzor]

Yeah I'm not sure. The major flaw in the study is the size of the GP and there is no/little water current. With normal reef-tank current the results could be completely different, it's hard to trust it either way, though.

In my opinion, the live feed was more successful because it is moving - therefore it has incredibly higher chance of encountering a coral polyp.

[Amphiprion]

Sure, and that was something I had been thinking about while posting it, but whether or not it is worth it, I don't think so. Of course, live feed is almost always going to be better in that regard, since it does seem to increase prey capture rates. The issue I see with GP is that I don't know if the polyps ingest and digest it, or if it is expelled or ignored outright. Maybe it would be worthwhile to see if you can buy a small amount from someone and conduct some observations yourself before using it on the main tank. Though, you've probably got more than adequate export mechanisms on your display, so you could experiment a bit more there. Size difference shouldn't play a terribly large role by comparison (at least with that coral), considering the size of the nauplii, which were accepted. That doesn't mean that size doesn't play a role overall, which obviously it does, but when comparing the two foods, it doesn't seem to be a major factor. My first step if I were to pursue this, again, would be to run a few trials and observations to see what you come up with. You'd want to monitor and record water quality to make sure it changes as little as possible while you do it, though, to account for anything that may influence growth. Finding a good live food of the same general size would make for a good comparison (a similar assortment of rotifers?). This would be a good way to decide it.

[Logzor]

Excellent points. A real comparison between the GP and live feed in my own system would be an interesting experiment. I remember reading a post by Eric Borneman, he said that there was little, if any, real gut analysis of sps corals. It is really hard to say what they prefer. So far it seems like everything regarding sps and food is hearsay, no concrete evidence. The AA article, of course, leads use to believe that they prefer live food, though.

In my initial use of GP I was pleased. I had been having issues with, what I would call lack of nutrients, resulting in pale SPS corals. I used them for 2 weeks, 1/16 tsp nightly - skimmer off.

During this time my tank was stable, 2 - part is dosed throughout the day via LMIII. Kalk is top-off evenly throughout the day, also.

I am certain that my colors improved - but I have no evidence there was a relationship between that and the GP's. Regardless, I am not worried about pollution in my tank, BB with and over-sized skimmer has advantages.

A true experiment between GP and live feed would be a huge challenge. Raising the live food alone would be an undertaking, let alone developing a good system to measurable parameters related to growth/color/PE.

[stanlalee]

Just going from the results, I wouldn't. It is very evident that, at least in Pocillopora, that there is little interest in that food.

I didn't get that from the testing at all. they stated the food stayed in the water column for only an hour before sinking to the bottom while the live food naturally was available the whole time it was present. based on the increased survival rates of the golden pearl fed corals and the fact its of the same species of what was clearly consumed live I'd just as well conclude it fed algae and not the corals because except for the first hour its simply dead matter on the bottom. In my bare bottom with 80x + turnover there's virtually no chance of that happening.

[Amphiprion]

I didn't get that from the testing at all. they stated the food stayed in the water column for only an hour before sinking to the bottom while the live food naturally was available the whole time it was present. based on the increased survival rates of the golden pearl fed corals and the fact its of the same species of what was clearly consumed live I'd just as well conclude it fed algae and not the corals because except for the first hour its simply dead matter on the bottom. In my bare bottom with 80x + turnover there's virtually no chance of that happening.

I still don't think you'd get much of an actual feeding response with the golden pearls. I think that applies to many of the artificial foods, honestly. If you look carefully, the variance in survival rates compared to the control are not significant. Even further, it states that differences survival rates were still not statistically significant with live food, as well. If it were me, I'd personally stick to oyster eggs, rotifers, etc., as well as a good, productive refugium to hopefully supply invertebrate larvae.

Edit: Then again, that's my perspective. I think a better experiment would shed more light on the subject.

[Logzor]

How different are oyster eggs from golden pearls?

I definitely get a feeding response. The polyps on my huge scroll coral don't come out with normal pellet feedings. They do, however, come out in full force when I add golden pearls.

[Amphiprion]

I meant actual ingestion, etc. by feeding response. Oyster eggs are different from GP in that they are an already whole, natural food. I don't think GP will elicit the exact same feeding behavior and ingestion that such foods, like oyster eggs, will. I've noted much of the same with anemones, though there are exceptions.