Keys to coral growth: FYI

Sk8r

Staff member
RC Mod
1. sufficient nutrient. For softies, feeding your fish generally feeds the corals---either first-run or recycled through the fish. Food also comes from photosynthesis: conversion of light to sugars. LIGHT enables coral's zooxanthellae (light-using elements) to do that. If you ever see a coral exude brown stringy stuff, that is a coral losing its zooxanthellae [zo-zan thelly], which can be due to too MUCH light, and this damage is hard to repair. SPS stony doesn't like particulate in the water: it's extremely light-reliant, and a very strong skimmer is needed to keep the water crystal clear for SPS. LPS is happy to scarf down floating bits, and some LPS like plate even takes in whole morsels of food. Just remember: LIGHT produces nutrient---and properly changed seawater is full of minerals besides pure salt [sodium chloride]---so your lights and your water changes are major items feeding your corals.

2. stability. On a basic level, most corals like to be part of the rockwork---solidly attached, untouched by human hands (wear exam gloves) and never bumped or nudged or allowed to wobble around in the current. They don't like to be blown hard by current so that food doesn't stay near; they don't like to be under-served by current so that food never comes their way. A chaotic mild flow is generally good. One exception to the 'stable ground' rule is plate coral, which actually gets up and moves about the sandbed, stony center and all. SECOND point of stability is same-old, same-old: the same temperature, salinity, and chemistry maintained over time. Now, coral IS responsive to day-night cycles and moon cycles---they even time certain things by those cycles, but the cycles themselves are stable and ongoing and dependable, over thousands of years. They also cope with weather, like being clouded up, or even having rain change the salinity a little. But in general, have an ATO and do your changes on schedule.

3. territoriality: yep, even corals. Remember that some softies like mushrooms tend to relocate themselves if unhappy with light or current. And softies when annoyed or ambitious---spit. They spit chemical that discourages other corals. In the ocean, this only affects corals down-current of them. In our tanks goes-around, comes-around. Often. Carbon can remove this spit from the goes-around, so use it. But be very careful what you put downwind of a leather or other strong spitter. LPS doesn't so much spit as target its unhappiness with tentacles, that can reach 6" downwind---or straight up, to my amazement. I've seen a bubble perform this trick. SPS is pretty well defenseless, though among their own kind there are corals like the Green Slimer, aptly named. Mostly just keep them out of everybody's reach.

4. a just-fragged coral of any kind is pretty annoyed, and may exude 'unhappy' chemicals that will share the snit with all the neighbors. But it is also true that an injured coral heals best in the GOOD water in which it's been living---that stability thing, the dislike of changes. Try to put a wounded coral back where it was, unless that's not a good place for it. Same as you like your own bed and chicken soup, just let it recover...but if it's a softie, definitely run carbon, because it will not be happy. If you see corals suddenly shrivel and close, that's often what's going on: spit.

5. particularly watch your alkalinity: I keep mine at 8.3. Low alkalinity affects the water's ability to handle and carry the elements your corals need for comfort and food, and that's true for soft and stony corals---and fish. EVERYTHING wants stable alkalinity: that governs the basic behavior of seawater, and if it's off, ain't nothin' happy.
If your calcium is below 420 for a stony coral, again, fix that. If your magnesium falls below 1200 your alk and cal will plummet. Keep it around 1300, 1350. Once stony starts feeding it will yank calcium out so fast you will need a supplement, which for a new tank is generally satisfied by putting kalk in the topoff water and having an Autotopoff. If you have a big tank, big reef, you may need a calcium reactor to keep up with the demand, but that's not until kalk doesn't do enough for you.
 
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Hmm ALMOST every night when leds are almost off just 1% blues.. all LPS corals + nems close up not sure why could it be the spit thing (all corals are spaced decently apart) or just a night time thing? I have BRS dual reactor with carbon I just thought it was kinda normal?
 
Sk8r, I am still battling my hair algae issue. I did however see a couple of my LPS a few weeks back before things got really bad, extracting brown string. Could that be due to too much light or the excessive nutrient issue causing hair algae? My lighting is a kessill a-150 sky blue on a 28g jbj nano.

Thanks!
 
I would tend to suspect light intensity. I'm running Radion G3 pro at 9" above the water, on 55% intensity, with corals 10" below the water line. The program I'm using is a mostly blues scaling up to daylight white and down again to the violets.

Just as a note, when starting corals out in a tank, I tend to put softies down virtually on the sandbed, and I find that about a foot to 9" below the water surface is a good start for most lps. Sps will likely to want top of rocks, but be conservative about it. The one exception to moving a coral is when you need more or less light on it, within the first few weeks. And pay attention to how the store had it placed.

Never, ever, ever, ever buy a coral without knowing what class (sps/lps/softie) it is and pretty well what its name is: sps is often 'well, I think it's a ...[fill in blank,] because you can never tell for sure until you see how it makes its branches in a big colony---sort of like telling the tip of an apple tree branch from a crabapple when it's just a twig. It'll become apparent as it grows up. Same with sps. But you CAN ask whether an sps is branching, shelving (like a lettuce plant), or encrusting (like cake frosting). And that will help you plan where it should be. {If you are crazy enough to take on sps, [I've been there] I recommend starting with the montiporas, which do all 3 types and come in many colors.]
 
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All due respect to Sk8r I would add the following:

If you want your LPS to grow - feed them. Any LPS with a mouth (and they all have mouths to one extent or another) can and will eat.

Some examples:

I had a brain coral I ended up calling Jaba the Brain because I would regularly feed it pieces of frozen silversides. It went from about 4" to over 8" before it had to find a new home because it was too big for the tank. I fed it about once a week.

I would feed my Acan's about 3 times a week. I would get 2-4+ heads of growth per month out of them. I actually had to stop feeding several colonies because they got too big

Sun corals grow fast. But you have to feed each head. And as they grow there are more heads to feed. Unfortuately this was She Who Must Be Obeyed's favorite coral. So it got fed. A lot. ;)

Blasto's will multiply faster with food. No where near as fast as Acan's which are like weeds but they will grow.

Zoa will grow like weeds too.

As will frog spawn, bubbles, and the like.

My favorite food to use was Sallifert high energy pellets. It has been discontinued but a good replacement is the Coral Frenzy reef pellets. I would use a pipette to target feed after feeding the fish to stop them from grabbing the pellets from the corals.

Also if you keep an anemone it too loves to be fed and one way to keep it where you want it is to regularly feed it. It will associate the spot it is in with food. It can also split more often so be on the lookout for that.

A fun side fact about clams. They are also filter feeders and make a good part of your overall nitrate removal program. They don't take up a lot of nitrate but every bit helps and they are a nice addition to the tank. If you look at clam farms in Asia for clams used for food (same clams as we buy for our tanks) you will find the farmers dumping fertilizer in the ponds to increase growth.

Some examples of before and after feeding:














And SPS will do fine if you feed your LPS. Just keep the water clean via skimming, carbon, and water changes.



 
As above, yes, morsels, as in small bites, of solid food---thank you for the clarification and thank you for the pix and info. Beware of flooding your tank with doses of this and that chemical, which can create problems, but targeted feeding, using, eg, a long probe, is productive for some species. I had a short-tentacle plate (before a fighting conch accidentally did it in) that would accept either sinking pellet or quite happily, a cross-section slice of table-sized raw shrimp. Amazing how that little coral could accommodate a piece of food much larger than its mouth.

Let me clarify: target feeding, if a coral will accept it, is great. A long probe or suction tube or some means to get it to the coral delicately is one of the best means, depending on where the coral is sited. The thing NOT to do is to run out and get every chemical supplement and broadcast food available. If you put a morsel of food right on the doorstep of a coral that's amenable to target feeding, you will likely see a feeding response. There are some broadcast foods, as well, that do well without messing your chemistry up. Euphyllias, in particular, do well with ground krill---I just put dried jumbo krill into an old coffee grinder. And the fish rather appreciate it too. It's the chemical supplements that can put your tank in a genuine mess.

One of the best ways to get food where you'd like to is a non-mouth pipette. I used to have access to lab equipment, and a length of hollow glass like a plastic soda straw is wonderful for this. Stop the top with your finger---you know the trick with a glass of soft drink---and you can move a little bit of liquid and deposit it where it needs to go. [Never pipette by mouth in your tank or in chemicals. Evah!]
 
Yes absolutely. Target feeding only. Don't dump a bunch of crap that is advertised as 'coral food' into the tank. For the most part the corals aren't going to get it because it will be sucked up by the filters or just hang.

Also be aware that much of the frozen food sold is frozen in water that is high in nitrates and phosphates as well as TDS. It is best to defrost the food, strain it, rinse it, and then put it in the tank.
 
You do have to be careful with LEDs. Many assume blue light is very gentle. Not so.
 
Great info!
However I have a problem I hope you guys can help me with: my Pavona (an SPS).
It's turning BROWN!!! It's still fuzzy - but it's NOW mostly brown!!!
Water results, fresh hot off the press:
My pH is 8.3
My Calcium is 425.
Alkalinity is 8, dead smack on the nose.

NO nitrates, nitrites OR ammonia!!


I have two (2) T5 white and 2 T5 actinic blue lights all at 56 watts each
AND 2 LEDs, - a CURRENT 12K diamond white AND an actinic blue!!
FLOW: three (3) powerheads running at 1500 GPH!!

Fish are doing great, all my other corals (mostly softies) doing good!

ANY THOUGHTS, anyone ????????? :uhoh2:
 
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It may be too much food. Brown is overproduction of zooxanthellae, and it could be too much light, too much nutrient, or a coral that for some reason is protecting itself, maybe even from a neighbor.
 
Look closely...I call this photo 'Anywhichway you can...' ---that's a bubble coral reaching a tentacle straight up to try to sting a pocillopora (not in view) on the shelf above---and current is not preventing it.
IMG_5127.jpg
 
:cool: Those corals are gorgeous! I'm envious!
Anyway, thanks for the info sk8r!
I was thinking that too - my T5s may be burning it. I'll try running just my LEDs for a week while observing to see what happens. Here's to hoping! :cool:
 
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