Low nutrients vs. starving a reef

[Aaron]

What are peoples thoughts on feeding a reef tank? How much and with what?

I have aggressively run carbon and GFO, along with my oversized skimmer pretty much since day one.

Tests for nitrate and phosphate have always come back as undetectable, but since there is some algae in the tank, I assume there are nutrients but they're just being taken up by the algae immediately.

The reason I am asking is because some of my softies and LPS are not nearly as full looking as they used to be, and a couple of my sps have lost their color. They aren't brown, they grow fast, and they have full polyp extension, they just don't have any color at all (mostly the purple ones seem to do this on me the most).

Yellow, red, and green are not a problem to keep, and even blue is becoming easier (especially on new growth).

All things considered, I am wondering if I might be stripping too much out of the water and the sps are not getting the nutrients they need (though I understand they are mostly light dependent).

I don't think lighting is the issue since most of my sps are toward the top of a 12" deep tank with 6x39w T5 on them (ATI bulbs), that is unless they are getting TOO much light.

Anyone have any insight? I know coloration is a complicated subject, but I sure would like to be able to keep purples purple, and white can't be healthy.

[Jon Lazar]

Borneman frequently refers to studies showing that most IP corals derive most of their nutrition from captured prey, not light. I'm not sure that's your problem, but it may be one factor.

 

I try to feed as much food as I can, of as many different kinds and sizes, without letting nutrients get too high. I like cyclopeeze, frozen rotifers, and the two smaller sizes of golden pearls. I mix up a few ounces and target feed my NPS corals, then let the rest float around for a while before the pumps come back on. I also heavily feed the fish, and much of the flake, peelet, and mysid gets captured by corals as it floats around the tank. My water looks like a snowstorm during feeding.

[OUsnakebyte]

I agree with Jon. I think most corals are underfed - stonies in particular are a battery of stinging cell and digestive glands and are meant to eat. Yes, they do derive most of the sugars they need from the zoox, but they really should be fed size-appropriate food.

 

I like the food Jon listed above, in addition to newly-hatched, decapsulated brine shrimp.

 

Also, I like to feed a few hours after lights out, or very early in the morning, as that seems to be when most stonies are actively feeding.

 

Cheers

Mike

[Jon Lazar]

I like the food Jon listed above, in addition to newly-hatched, decapsulated brine shrimp.

 

Also, I like to feed a few hours after lights out, or very early in the morning, as that seems to be when most stonies are actively feeding.

 

 

Concur with both points! Until recently I've been chain-hatching batches of baby brine shrimp and dumping them into the tank. The pods will eat any that the corals miss.

[Aaron]

Thanks guys, I think you just confirmed my suspicions last night. I have decided that I'm trying to maintain far too sterile an environment. I started thinking about it and really almost feeling guilty because I know at some point these critters must get hungry. That and I think I can attribute some of the problems I've had to inadequate feeding.

Well, time to go home for the day and start polluting the tank

[Chad]

Remember, that a step change can result in unintended consequences... In the case of feeding, I have often seen small cyano outbreaks occur shortly after changing something like a feeding regimine. Keep in mind that your corals and system need a little time to react, and sometimes the fastest things to react are the cyanos and other algae - not a bad thing, and completely normal, in a healthy tank it is short lived.

 

I fully agree with Jon and Mike on this, feeding is good (and your tank can probably take a lot more than you think it can). But I would start slow and let your system respond a bit before upping the food amount to minimize the chances of a "false alarm" that you are feeding too much, when you actually are not.

Edited March 7, 2011 by Chad

[Aaron]

Thanks Chad - I think that's some of the best advice I've gotten with regard to feeding, and here's why.

I have this pseudo-scientific theory that part of the problem with my system is a self-inflicted imbalance. What I mean is that there's always a "knee-jerk" reaction when some kind of algae or cyano appears. It looks unsightly, has the potential to take things over, and therefore must be eliminated - i.e., more ferric oxide, more carbon, bigger skimmer, larger water changes. There's a part of me that's beginning to recognize these things as a very unatural approach, not that there's anything natural about a box full of water in my livingroom with corals in it, and I also realize they are all tools when properly applied. That being said, maybe it isn't always appropriate to apply them. By aggresively chemically removing phosphate, what happens long-term?

In my mind it's fair to say that other simple organisms that aren't phosphate limited take over. What happens with bacterial populations? I am actually wondering what the outcome would be running my system with JUST: a properly functioning skimmer, adequate lighting, and 10-15% bi-weekly water changes along with regular feeding of the right foods.

I assume that many of the "undesirable" lifeforms would ultimately come and go, outcompeted by desirable ones.

Maybe I have things all wrong, and this vision of a reefkeeping "nirvana" is completely unrealistic, but there are a million different products out there, thousands and thousands of dollars to spend.

....leading the hobbiest down the path to an extremely complex and expensive system that will ultimately face most of the same problems and challenges that my little odd dimension 40 gallon will have.

Who knows....no matter how much I learn, I may never have the real answers.

[Chad]

I don't think you are far from the truth You pretty much just described my mantra! Make deliberate changes with expected changes that are compared to actual observations. Keep things as simple as possible, as complex as required, and be super-diligent with the basics of husbandry.