If you’re a regular reader of my blogs and have attended my presentations before, you know that I’m pretty much obsessed with feeding corals- in particular, “SPS” corals. Specifically, Acropora. The obsession arose after I came to the (dramatic) realization that I actually had to feed the darned things in order for them to grow and attain beautiful colors! No stony coral is entirely photosynthetic, to my knowledge. They derive nutrition from other food sources, some of which we as aquarists can provide directly. This is not such a bad thing, because interacting with your corals is pretty fun!
"SPS" corals are what those egghead scientist people call “mixotrophic”, which is a really fancy way of saying that they use photosynthetic capabilities throughout the production of symbiotic algae called zoxanthellae, as well as chowing down on other organisms. The zooxanthellae utilize CO2 and other substances that the corals really don’t need, and in turn, provide sugars and oxygen that coral use to grow. A high percentage- but not all- of the corals’ energy needs are met through this process. Ahh, cool!
"I'll have an order of light, zooplankton, and a dissolved organic matter chaser, please"
Oh, let’s just touch on everyone’s favorite subject- aquarium lighting, for a second- as it relates to “SPS” coral nutrition…Since “SPS” corals do use light to power their zooxanthellae, providing high quality light is super important. We’re not going to go into Sanjay’s turf and talk about who makes the best light; we’ll just say that you should employ adequate lighting for the corals that you wish to keep, and you should make sure that your water is clear enough to transmit light effectively, and that your lights are not excessively shielded by aquarium hoods, covers, or dirty protective glass covers. Keep stuff clean! You pay way too much for those fancy lights to not let them do their job effectively. Yes, this is the first time you’ve probably ever read about cleaning your hood off in an article about coral feeding.
We’ve talked about it before, and I’ll mention it once again- don’t obsess with keeping your water sterile…That thinking is soooo 1990’s it’s not even funny. It’s not necessary. If you still think that way, you might as well just start wearing flannel again and dusting off your Nirvana CDs..Okay, you could dust ‘em off anyways, but still. Wiping your water clean of all nitrate and phosphate is a really bad idea, as these materials are vital for metabolism in “SPS” corals. If you get too obsessed with lab-grade aquarium water, you can literally starve your corals to death in an attempt to keep them “happy.”
I’m now going to go on record as having said that I have changed my thoughts about protein skimmers and skimming over the years, especially since I’ve become involved in the commercial propagation of corals. I’ll say it: I think we over-skim our systems. I love skimmers, and I think they are a vital tool in helping provide excellent water quality for closed systems. However, good skimmers run on a continuous basis can effectively strip large quantities of dissolved organic matter out of the water. That’s organic matter that corals can utilize for growth. I have become an advocate of “frequent” skimming (like, a few days a week, or perhaps daily at night, to help remove CO2 and moderate day/night pH swings), as opposed to “continuous” skimming.
Oh, I’m straying (imagine that?)…The point is that having some dissolved organic material in the water is pretty important for coral nutrition and growth. That’s why you’ll hear reefers talking about “Vodka Dosing” (yeah, I laughed when I heard it the first time, too. I was thinking about endorsements: MACNA Presented by Absolut”, or “Absolut Reef Geek”…whatever..digressing again). The theory behind dosing is that Vodka provides a source of carbon to the corals, which can become a growth-limiting factor in coral husbandry.
Remove this stuff 24/7/365, and all of those poor little Acros are gonna be REALLY hungry!
The take-away here: Provide your “SPS” corals with a source of carbon and dissolved organic matter, such as nitrate. Don't take it all out by hyper-skimming. How to best accomplish this? Stock with fish. Feed the fish. Let them poop. Corals like fish poop. Yup. Besides, watching your prized tang poop in your reef is at least as interesting as adding a shot of Vodka every day, right? Maybe? Ok…maybe not, but you get the idea…
We get by with a little help from our friends...
And of course, amino acids play a very important role in coral health and in particular, their colors. ‘SPS” corals benefit from amino acid dosing, as it prevents them from bleaching, and spurs the production of pigments that help regulate the amount of light they receive- kinda like natural “sunblock.” Of further interest is the fact that scientists have noted that corals uptake amino acids during daylight hours, as this uptake is stimulated by light. As Mr. Spock would say, "Fascinating..."
Finally, and certainly not the least important: Intentionally and directly feed your corals. Feed the heck out of ‘em. Feed them every day if you can. Sure, use some logic here. Do it when the circulation pumps are off, and do it during the “dark” hours on your reef, when they are in “feeding” mode…
What to feed your “SPS” corals? I am a huge fan of things like oyster eggs, Cyclop-eeze, and other very small zooplankton-based feeds. There are quite a few great commercially available coral feeds out there…just ask any reefer!
There's a reason why this coral is so "hairy"...it's a "chow hound!"
Remember, feeding corals is a multiple-pronged approach. You can allow some organic material to be produced by fishes, keep some of it in your system by not going bonkers with your skimmer, and by direct feeding prepared foods to your corals at the appropriate time of day. And don’t fogey that you should make sure that other environmental parameters, such as the temperate, calcium level, and alkalinity are stable. Don’t obsess over numbers, obsess over stability within a given range! All of the great coral food in the world won’t help if your water chem is bouncing around like a 14 year old girl at a Justin Bieber concert! Keep it stable.
Don't blame "The Biebs" for your unstable water chem! It's not his fault. Seriously.
And change water…Yep, even with my new-found love of “frequent skimming”, I still will implore you to perform regular water changes, as they will remove gross particulate matter, dissolved metabolites not utilized by (or even produced by) the corals themselves. Also, major and minor trace elements, all of which are important to “SPS” corals, are replenished at the correct levels when you perform regular water changes with a high quality synthetic salt mix.
SO that’s my “more than two cents” on “SPS” coral feeding. Bottom line- Do it. DO it frquently. Do it well.
I am 100% certain that all of you highly experienced reefer peeps out there will have lots of pearls of wisdom to add on to this little rant, so please…have at it!
Go love your reef, feed your corals, and…Until next time…
Stay Wet
Scott Fellman
Unique Corals
"SPS" corals are what those egghead scientist people call “mixotrophic”, which is a really fancy way of saying that they use photosynthetic capabilities throughout the production of symbiotic algae called zoxanthellae, as well as chowing down on other organisms. The zooxanthellae utilize CO2 and other substances that the corals really don’t need, and in turn, provide sugars and oxygen that coral use to grow. A high percentage- but not all- of the corals’ energy needs are met through this process. Ahh, cool!
"I'll have an order of light, zooplankton, and a dissolved organic matter chaser, please"
Oh, let’s just touch on everyone’s favorite subject- aquarium lighting, for a second- as it relates to “SPS” coral nutrition…Since “SPS” corals do use light to power their zooxanthellae, providing high quality light is super important. We’re not going to go into Sanjay’s turf and talk about who makes the best light; we’ll just say that you should employ adequate lighting for the corals that you wish to keep, and you should make sure that your water is clear enough to transmit light effectively, and that your lights are not excessively shielded by aquarium hoods, covers, or dirty protective glass covers. Keep stuff clean! You pay way too much for those fancy lights to not let them do their job effectively. Yes, this is the first time you’ve probably ever read about cleaning your hood off in an article about coral feeding.
We’ve talked about it before, and I’ll mention it once again- don’t obsess with keeping your water sterile…That thinking is soooo 1990’s it’s not even funny. It’s not necessary. If you still think that way, you might as well just start wearing flannel again and dusting off your Nirvana CDs..Okay, you could dust ‘em off anyways, but still. Wiping your water clean of all nitrate and phosphate is a really bad idea, as these materials are vital for metabolism in “SPS” corals. If you get too obsessed with lab-grade aquarium water, you can literally starve your corals to death in an attempt to keep them “happy.”
I’m now going to go on record as having said that I have changed my thoughts about protein skimmers and skimming over the years, especially since I’ve become involved in the commercial propagation of corals. I’ll say it: I think we over-skim our systems. I love skimmers, and I think they are a vital tool in helping provide excellent water quality for closed systems. However, good skimmers run on a continuous basis can effectively strip large quantities of dissolved organic matter out of the water. That’s organic matter that corals can utilize for growth. I have become an advocate of “frequent” skimming (like, a few days a week, or perhaps daily at night, to help remove CO2 and moderate day/night pH swings), as opposed to “continuous” skimming.
Oh, I’m straying (imagine that?)…The point is that having some dissolved organic material in the water is pretty important for coral nutrition and growth. That’s why you’ll hear reefers talking about “Vodka Dosing” (yeah, I laughed when I heard it the first time, too. I was thinking about endorsements: MACNA Presented by Absolut”, or “Absolut Reef Geek”…whatever..digressing again). The theory behind dosing is that Vodka provides a source of carbon to the corals, which can become a growth-limiting factor in coral husbandry.
Remove this stuff 24/7/365, and all of those poor little Acros are gonna be REALLY hungry!
The take-away here: Provide your “SPS” corals with a source of carbon and dissolved organic matter, such as nitrate. Don't take it all out by hyper-skimming. How to best accomplish this? Stock with fish. Feed the fish. Let them poop. Corals like fish poop. Yup. Besides, watching your prized tang poop in your reef is at least as interesting as adding a shot of Vodka every day, right? Maybe? Ok…maybe not, but you get the idea…
We get by with a little help from our friends...
And of course, amino acids play a very important role in coral health and in particular, their colors. ‘SPS” corals benefit from amino acid dosing, as it prevents them from bleaching, and spurs the production of pigments that help regulate the amount of light they receive- kinda like natural “sunblock.” Of further interest is the fact that scientists have noted that corals uptake amino acids during daylight hours, as this uptake is stimulated by light. As Mr. Spock would say, "Fascinating..."
Finally, and certainly not the least important: Intentionally and directly feed your corals. Feed the heck out of ‘em. Feed them every day if you can. Sure, use some logic here. Do it when the circulation pumps are off, and do it during the “dark” hours on your reef, when they are in “feeding” mode…
What to feed your “SPS” corals? I am a huge fan of things like oyster eggs, Cyclop-eeze, and other very small zooplankton-based feeds. There are quite a few great commercially available coral feeds out there…just ask any reefer!
There's a reason why this coral is so "hairy"...it's a "chow hound!"
Remember, feeding corals is a multiple-pronged approach. You can allow some organic material to be produced by fishes, keep some of it in your system by not going bonkers with your skimmer, and by direct feeding prepared foods to your corals at the appropriate time of day. And don’t fogey that you should make sure that other environmental parameters, such as the temperate, calcium level, and alkalinity are stable. Don’t obsess over numbers, obsess over stability within a given range! All of the great coral food in the world won’t help if your water chem is bouncing around like a 14 year old girl at a Justin Bieber concert! Keep it stable.
Don't blame "The Biebs" for your unstable water chem! It's not his fault. Seriously.
And change water…Yep, even with my new-found love of “frequent skimming”, I still will implore you to perform regular water changes, as they will remove gross particulate matter, dissolved metabolites not utilized by (or even produced by) the corals themselves. Also, major and minor trace elements, all of which are important to “SPS” corals, are replenished at the correct levels when you perform regular water changes with a high quality synthetic salt mix.
SO that’s my “more than two cents” on “SPS” coral feeding. Bottom line- Do it. DO it frquently. Do it well.
I am 100% certain that all of you highly experienced reefer peeps out there will have lots of pearls of wisdom to add on to this little rant, so please…have at it!
Go love your reef, feed your corals, and…Until next time…
Stay Wet
Scott Fellman
Unique Corals
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