Why are my corals darkening?

[Phyber]

This is my first attempt at SPS. I've gotten a few frags of different species to see what works. My birdsnest, stylophora and monti cap seem fine and I can see growth. I have a traditional acropora that seems fine, no distinct color change since purchase and good polyp extension. However, I have a green and purple staghorn that has seemingly darkened up a ton. I do see polyp extension. The fluorescence decline is what is so evident to me.

Water tests show:
SG: 1.026
Alk: 10
Cal: 485
Mg: 1390
Nitrate: Undetectable (I have an older API kit, waiting on new kits)
Phosphate: Undetectable (I have an older API kit, waiting on new kits)

I had been doing 20g bi-weekly water changes, but eased up on them once I was needing a 2 part regimen to keep up with Alk and Cal. Water changes couldn't keep up with my schedule.

This is the frag when first placed in the tank on September 6, 2019, followed by today September 29, 2019.

Tank is a 65g (36"w x 18"d x 24"h) lit by two AI Prime HD's running a modified BRS AB+ program for 12 hours a day.

 

[Ron Reefman]

Corals can change colors. Most hardly at all, some can change a lot and it depends on that parameter changed to make it morph.

I have green wagon wheel zoas I bring home from the Florida Keys. Under ordinary led light in my tank (10" or more deep) they look perfectly normal. Set them up higher and give them more PAR and in a couple of weeks they lose the wagon wheel spokes and turn sky blue! Move them back down and in a few weeks they go back to being green.

 

[Phyber]

Corals can change colors. Most hardly at all, some can change a lot and it depends on that parameter changed to make it morph.

I have green wagon wheel zoas I bring home from the Florida Keys. Under ordinary led light in my tank (10" or more deep) they look perfectly normal. Set them up higher and give them more PAR and in a couple of weeks they lose the wagon wheel spokes and turn sky blue! Move them back down and in a few weeks they go back to being green.

I think I'm running a higher alk and lower mag than the tank this was fragged from. I also think the parent tank might have had higher par lights, but hard to say (kessil 700's vs my primes?)

So as long as they aren't turning white they're still good to go?

 

[JCOLE]

I would get a better kit such as red sea or salifert for Nitrates and Hanna for ultra low phosphates. If your numbers are correct then the corals could be starving. You need some Nitrates and phosphates to keep your colors up. Especially when running an Alk around 10dkh. With higher Alk and lower nutrients then you run the risk of burning the tips.

 

[Charlie’s Frags]

2 primes at the ab+ program on a 65 gallon won’t be near enough light to keep Acropora alive. That’s probably why they’re browning. They’ll most likely start to look dried out soon which means death will follow after.

 

[Phyber]

P

I would get a better kit such as red sea or salifert for Nitrates and Hanna for ultra low phosphates. If your numbers are correct then the corals could be starving. You need some Nitrates and phosphates to keep your colors up. Especially when running an Alk around 10dkh. With higher Alk and lower nutrients then you run the risk of burning the tips.

Thanks! That's another reason I was glad to slow down the water changes. I am diligent with changing the filter socks and I skim a bit wet. I have my eheim feeder set for twice daily a mix of flake and Spectrum pellets for the fish, and I use some LRS frozen frenzy a few times a week. Just don't want to tip the scale and start issues with nuisance algae.

 

[Phyber]

2 primes at the ab+ program on a 65 gallon won’t be near enough light to keep Acropora alive. That’s probably why they’re browning. They’ll most likely start to look dried out soon which means death will follow after.

My schedule still has room for increase, should I start maxing out my blues and then add white? I like seeing the more blue look if the tank vs white

 

[Charlie’s Frags]

My schedule still has room for increase, should I start maxing out my blues and then add white? I like seeing the more blue look if the tank vs white

You would probably need to max out the white for 4-6 hours of your schedule to produce enough par. I have 2-52 HD’s over my 50 gallon display and 2-26 HD’s over my 29 gallon frag tank. 2-26 HD’s at the ab+ on 29 gallons produced about 250 par 6” below the surface. You have almost half the par power over twice the volume. Whites do produce a LOT more par though. So you could crank those up when you’re not home and ab+ it for viewing.

 

[JCOLE]

P


Thanks! That's another reason I was glad to slow down the water changes. I am diligent with changing the filter socks and I skim a bit wet. I have my eheim feeder set for twice daily a mix of flake and Spectrum pellets for the fish, and I use some LRS frozen frenzy a few times a week. Just don't want to tip the scale and start issues with nuisance algae.

I would feed more and either leave your socks in longer or remove them all together. Also, run your skimmer dry or run for 12hrs on and 12hrs off. Need to start getting nutrients showing on the test kits. Algae is natural and is a sign that your tank is getting nutrients. Remember algae and healthy corals is better than a clean sterile box of water and no corals.

 

[Charlie’s Frags]

I would feed more and either leave your socks in longer or remove them all together. Also, run your skimmer dry or run for 12hrs on and 12hrs off. Need to start getting nutrients showing on the test kits. Algae is natural and is a sign that your tank is getting nutrients. Remember algae and healthy corals is better than a clean sterile box of water and no corals.

I agree 100%, but none of this will matter if you don’t provide enough light. Acros will stress, starve and then die.

 

[Phyber]

You would probably need to max out the white for 4-6 hours of your schedule to produce enough par. I have 2-52 HD’s over my 50 gallon display and 2-26 HD’s over my 29 gallon frag tank. 2-26 HD’s at the ab+ on 29 gallons produced about 250 par 6” below the surface. You have almost half the par power over twice the volume. Whites do produce a LOT more par though. So you could crank those up when you’re not home and ab+ it for viewing.

I might try that 4 hour noon ramp up for whites. I was debating on renting a part meter but since I'm really only seeing one coral with issue I wasn't sure

 

[JCOLE]

I agree 100%, but none of this will matter if you don’t provide enough light. Acros will stress, starve and then die.

By the looks of it they are already starving. I agree on the lighting but if he cranks them up any more without upping the nutrients then those tips are going to burn even more. He needs to hit them with the one-two punch. Get them nutrients up and drop the sun on them.

 

[Phyber]

I guess I've always had it in my head that sps needs such clean water... That I'm gumming it up when I feed a bit much or don't stay on top of water changes and maintenance.

My first time with a reef tank was during the ULN phase, so that's still engrained in me

 

[Charlie’s Frags]

Give them plenty of fish poop and light

 

[JCOLE]

I guess I've always had it in my head that sps needs such clean water... That I'm gumming it up when I feed a bit much or don't stay on top of water changes and maintenance.

My first time with a reef tank was during the ULN phase, so that's still engrained in me

You do want "clean" water. You just want a balance between everything. Phosphates help the corals nutrition but too much will stop their growth. Too little or 0 phosphates will starve them to death. Same with Nitrates. Nitrates help corals with their color. However, too much or little is not a good thing as well.

 

[JCOLE]

Give them plenty of fish poop and light

Yeah we get it. You have beautiful pieces. Quit rubbing it in. Lol

 

[Charlie’s Frags]

Yeah we get it. You have beautiful pieces. Quit rubbing it in. Lol

I apologize if my pictures come off as rubbing it in, as that’s not my intention. I’m simply showing I practice what I preach and my method is effective. There are a lot of ppl that give advice with zero proof that they even keep Acropora, or don’t show their state of health if they do. It seems you were joking with the lol, but if anyone else is offended by my pics I can try to take them down.

 

[JCOLE]

I apologize if my pictures come off as rubbing it in, as that’s not my intention. I’m simply showing I practice what I preach and my method is effective. There are a lot of ppl that give advice with zero proof that they even keep Acropora, or don’t show their state of health if they do. It seems you were joking with the lol, but if anyone else is offended by my pics I can try to take them down.

Yes, it was meant as a joke. Sorry if it came across otherwise. In no way am I offended and I always enjoy your pictures and I think you have awesome corals. Do not take them down man and keep posting!

 

[DuckSlayer627]

2 primes at the ab+ program on a 65 gallon won’t be near enough light to keep Acropora alive. That’s probably why they’re browning. They’ll most likely start to look dried out soon which means death will follow after.

+1. Definitely need more light. 2 Primes are not much for Acro's. And the fish poop will also help.