SPS color fading

VTBig053 · Mar 27, 2018

The SPS (multiple species of Acro) in Fluval EVO 13.5 have recently begun losing color. Example, Myagi Tort went from nice deep blue branches to purple and now a pastel/lavender color. This isn’t the only piece that has faded over the past 2-3 weeks. My NO3 recently bottomed out to 0 about two weeks ago (testing on red sea kit) after using Vibrant to treat a hair algae problem. I have never had any PO4 register using a salifert kit. I always assumed there was some PO4 in the tank because I can grow algae like a champ

However, I am starting to wonder if it really is at zero.

I’m pretty sure the cause of the fading is nutrient related since my color was still pretty good a few weeks ago when I was testing NO3 at 2-5 ppm.

My question is really more about how to correct the problem. I am currently running filter floss, purigen, and chemi-pure elite (carbon) in a media basket in chamber 1 and chaeto with a reverse photoperiod grow light in chamber 2. I have tried increased feeding of both fish and corals but its not doing anything to raise the NO3 level. I think I am over filtering my water and want to start by removing the purigen to see if that will help to raise the NO3 levels before I explore NO3 dosing.

Anyone have any input on this? Am I heading in the right direction?

Thanks!

jda · Mar 27, 2018

The algae is outcompeting your corals. They are not at any risk, or anything, but the colors will come back when you get the algae under control and it is not gobbling up nutrients like crazy. Get some consumers to eat it.

You are not at zero or stuff would die... chances are a better P test kit would show some value.

ZaneTer · Mar 28, 2018

Sorry OP
I am going to offer advice in the opposite direction......sort of. I agree that you should get a grazer or two to get algae under control, not by starving it.

I disagree that you aren’t at zero. You are seeing clear signs of nutrient starvation and your test kits agree. It is extremely easy to bottom out NO3 or even PO4 with a modern tank setup. I have to dose for either nutrients to keep them at acceptable levels.
You will need to test for both NO3 and PO4 because while you are limited by nitrate currently your phosphate level may be rising at a rapid rate in the background.
It would also pay to keep a very close eye on your alkalinity level and adjust accordingly. If your corals cannot uptake the required nutrients then the cannot grow. If they cannot grow then alk demand plummets and your alk level in your tank will increase if you are dosing, you may even have to stop dosing alk for a short while.

If it makes you feel any better I bottom out regularly. My KH Director lets me know by showing the almost non existent alk demand. Nitrate takes a while to show when a coral is recovering or suffering from starvation....about 4 weeks in my experience. Phosphate shows a much quicker recovery or deterioration in about two weeks. Hope this helps.

Twolabs443 · Mar 28, 2018

I believe I have been in the same bot for the past month or two myself. Tank had been a softie tank for a while but wanted to try my hand at some SPS, I’ve seen good growth and PE but color has been somewhat subdued. I run A GFO reactor as well as a back chamber fuge on the AIO. Trouble I have is if I take the reactor offline or remove the cheato I end up with increased algae growth. Struggling to get things balanced.

ZaneTer · Mar 28, 2018

I believe JDA hit the nail on the head... get something to eat the algae. There are plenty of options if you have the tank space. You could manually dose your desired nutrient. Many of us do. Myself included.

jda · Mar 28, 2018

Once the algae is not thriving enough to consume every available nutrient, then you will have nutrient issues as they accumulate and grow. I would not dose anything until you are algae free and see what your numbers settle out towards. You are only low now because the algae is able to grab all that it can.

The P will not get too high... as the algae is converted into fish poo and there is not enough new algae left to consume it, then the aragonite will bind a lot of the PO4. Nitrate could be handled with anoxic bacteria if you have some real live rock or established sand a few inches deep... it just gets turned into N gas.

ZaneTer · Mar 28, 2018

JDA where did you get the aragonite but from? I agree that aragonite will act as a buffer but even it has a saturation point. I also didn’t see where the OP mentioned his tank containing aragonite as his sand media.

ZaneTer · Mar 28, 2018

Bear in mind that people can battle for months to get a hold of their algae problem. I personally would never risk the health of my corals just because I didn’t want to have to deal with some algae. Do you think your corals can last a few months in their current state?

jda · Mar 28, 2018

Dead/dry/live rock is aragonite too.

In a a test that I did, it was not yet saturated at 350x the tank reading at a ratio of 1 pound of aragonite to 5 gallons of tank water... it will hold a lot. My little tank collapsed on me before I could find a saturation point.
https://www.reef2reef.com/threads/phosphate-absorption-rates-in-aragonite.352405/

evoreefer1320 · Mar 28, 2018

With a small tank like that i would really keep a eye on the alk swings. What are you using to keep up the alk and calcium? color changes can be do to lack of nitrate in the water ect but also can be do to alk swings. Also remember phosphate removers can also mess with your alk and cause problems.

ZaneTer · Mar 28, 2018

That’s actually a very good read @jda

Currently OP has not posted his latest figures for PO4 or NO3. The advice was merely to keep an eye on it along with alkalinity.

He also does not state in anyway what media he is using for rocks or sand or even if it is bare bottom. We should be cautious until we know more details.

jda · Mar 28, 2018

You are not at true-zero on either N or P unless you are using organic carbon, GFO, LC or the like. The algae will always leave just a bit in the water column to drive the equilibrium - this is enough to keep everything alive. The bacteria will do the same. ...so will aragonite binding that always leaves some. Nobody ever had issues of too low of nutrients when just bacteria, fuges and water changes were around. If you are dosing any of these things, then your corals are in danger and you should probably stop.

Hannah Ultra Low Phosphorus would be needed for a better P reading. Nitrate is always just a guess.

My reef runs at .1N and .005-.01P all on it's own and everything thrives. I do this with just water changes, export of coral and chaeto/dragons[breath,tongue]. Naturally going low is no issue. Artificially going low can be if you get too low.

Reef Jeff · Mar 28, 2018

Never ceases to amaze me how we all have different experiences and opinions on this subject. I think part of the problem is the term “algae”. It is used to describe hair algae, Dino’s, cyano, etc. Some of these grow best when NO3 is zero and/or PO4 is zero.

Regardless, to the OP: If values bottomed out, remove some filtration especially the aggressive types and dose to get both NO3 and PO4 back up. You will also get many opinions on what the levels should be. In my experience, SPS do well with detectable PO4 and a few ppm of Nitrate. I assume yours is a mixed Reef. I run my mixed Reef at 1-2 ppm NO3 and .05-.08 ppm PO4. For me, SPS colors start to pale if the NO3 drops below 1 or if PO4 gets below .03. PO4 is a tough one to know where you are. Even with a Hanna ULR test and meticulous testing procedures two tests conducted back to back can be different by 5 or 6 ppb which translates to a difference of .015 to .018 ppm. I started running PO4 between .05 and .08 ppm to ensure I was never at zero. The reason for this is if you target .01-.03 as your goal, there really is no good test kit available today that can assure you are not at zero with a result of .01-.03. Now that I shoot for .05-.08, I know I always have some PO4 in the water.

VTBig053 · Mar 28, 2018

Thanks for the input all! I just realized I had a bunch of responses on this. Notifications aren't working for some reason. I have to run to a meeting but will post more info on the tank set up/parameters when I get back.

ZaneTer · Mar 28, 2018

jda said:
You are not at true-zero on either N or P unless you are using organic carbon, GFO, LC or the like. The algae will always leave just a bit in the water column to drive the equilibrium - this is enough to keep everything alive. The bacteria will do the same. ...so will aragonite binding that always leaves some. Nobody ever had issues of too low of nutrients when just bacteria, fuges and water changes were around. If you are dosing any of these things, then your corals are in danger and you should probably stop.

Hannah Ultra Low Phosphorus would be needed for a better P reading. Nitrate is always just a guess.

My reef runs at .1N and .005-.01P all on it's own and everything thrives. I do this with just water changes, export of coral and chaeto/dragons[breath,tongue]. Naturally going low is no issue. Artificially going low can be if you get too low.

I do not dose carbon or use GFO, I have only a skimmer and a fuge and on more than one occasion drove nutrients so low that coral died. I actually have to dose to keep nutrients up at an acceptable level. Many people share this experience.
You are making a very generalised statement here that many will disagree with. You speak as though traditional techniques were perfect yet on average the reefkeeper of today is far more successful than ever. This could be due to better quality lighting/skimmers/test equipment or any number of other factors.
I will not risk the health of my coral just because I may end up with more algae, I will get off my butt and begin pulling the algae out by hand if I have to.

Reef Jeff · Mar 28, 2018

jda said:
Once the algae is not thriving enough to consume every available nutrient, then you will have nutrient issues as they accumulate and grow. I would not dose anything until you are algae free and see what your numbers settle out towards. You are only low now because the algae is able to grab all that it can.

Not trying to start an argument as you clearly have experience based on your other posts I’ve read. I would like to describe what I experienced as it can also benefit the OP. I found the opposite of the above to be true. I was carbon dosing for a time to get NO3 and PO4 levels down after a tank reset. The rock had accumulated large amounts of PO4 over a few years of neglect. Post reset I bottomed out on both NO3 and PO4 just like you said can happen with these aggressive methods. Shortly after those values bottomed out I had explosive hair algae problems. I stopped carbon dosing as soon as I realized I had bottomed out the nutrient levels and started dosing NaNO3 and KH2PO4 while the hair algae was still a problem. The tank experienced a major decline in hair algae as a result of dosing NO3 and PO4. Even more interesting is I no longer needed carbon dosing to keep levels low. In fact to this day, I still have to dose NO3 as it always wants to go undetectable. I also still have to dose occasional PO4 even with a heavy feeding regime.

jda · Mar 28, 2018

I was not posting to you. This is not your thread. If you want to open one, we can try and figure out why stuff dies for you and the others that you talk about... and why it does not happen to the rest of us who use traditional techniques even with the same low parameter levels.

Reefing is the same as it as always been, at the core... those that embrace bio and chemistry and understand it... and those that think that somehow it has changed recently and that they can manipulate it with some tech. If understanding what natural methods of removing nutrients and their inability to actually, physically starve anything is traditional, then I guess that I am traditional.

jda · Mar 28, 2018

Reef Jeff said:
Not trying to start an argument as you clearly have experience based on your other posts I’ve read. I would like to describe what I experienced as it can also benefit the OP. I found the opposite of the above to be true. I was carbon dosing for a time to get NO3 and PO4 levels down after a tank reset. The rock had accumulated large amounts of PO4 over a few years of neglect. Post reset I bottomed out on both NO3 and PO4 just like you said can happen with these aggressive methods. Shortly after those values bottomed out I had explosive hair algae problems. I stopped carbon dosing as soon as I realized I had bottomed out the nutrient levels and started dosing NaNO3 and KH2PO4 while the hair algae was still a problem. The tank experienced a major decline in hair algae as a result of dosing NO3 and PO4. Even more interesting is I no longer needed carbon dosing to keep levels low. In fact to this day, I still have to dose NO3 as it always wants to go undetectable. I also still have to dose occasional PO4 even with a heavy feeding regime.

This is a very natural approach. Once you got the rock reset, it was able to bind/swap phosphate again as well as turn nitrate into NO3 gas. It appears that you went through three different phases - nasty rock part, getting the rock right again and now reefing with good, solid rock. What is needed in each one of these phases is different from one and another, IMO.

For example, in the nasty rock phase, the rock cannot have sufficient anoxic areas to combat nitrate, so the organic carbon was needed... but the rock is now fully capable. Mixing different techniques from different phases can be dangerous for some since they lack the breath and depth of experience to understand the nuance, but it appears that you played it quite well. Well done.

ZaneTer · Mar 28, 2018

It is certainly not the same. You think fixture and bulb choice hasn’t evolved? Or testing techniques and knowledge of husbandry? My tank is as traditional as it gets: T5, skimmer and fuge.
I respect the work you carried out testing aragonite and phosphate but that in no way proves that it is impossible to reach a level that is too low to maintain corals.