Retraction, color loss and rapid bleaching from edges

[Neuratox]

For the last two weeks I've been convinced that something was amiss in my 90 gallon display. I've noticed more retraction than is normal for my soft corals, the mushrooms are more frequently oozing guts out but pulling them back in later. In the last few days I've noticed that my acros are starting to brown out - they already weren't terrific, but were showing signs of improvement. Even my green slimmer is brown now. Now I've got acros that were doing great that are starting to die back from their leading edge where they were encrusting. There isn't even anything touching some of these. I've got no leathers or anything like that in the tank. Last week I tested twice and had 0ammonia, 0 nitirite, 0 nitrate, calcium was high at 500ppm, and alk was low at 6.7ppm (acros have been growing FAST) and I've been trying to adjust after having not noticed the low levels until about a month ago. pH is at 7.8 (usual for my tank). Salinity at 1.026 and temp at 78F. The tank is 2 years old and has been doing better than ever. I was worried something was in the water and put in carbon 2 weeks ago. 10% water change every week. No red bugs. No flatworms. Skimmer isn't working the best right now. Reduced from 6 fish to 3 a months ago.

 

[Neuratox]

I really need some help here. I'm watching many of my acros die a little more every day.
I tested parameters again today:
Ammonia: 0, Nitrite: 0, Nitrate: 0 I have some algae so I'm not super surprised that they're all at 0, but it the levels of algae are very minimal.
pH: 7.8, temp: 78F, Salinity: 1.026

Using Hanna checkers:
Alk 7.4, Calcium: 468ppm, phos: 0.16

The phos is WAY too high and would explain why I clean my glass every other day, however, I'm not familiar with high phos killing acros specifically.

I should be clear - the acros are dying from the edge, and only some of them. I broke off two pieces and have attached images from the dissection scope.

Unfortunately I don't have access to a better scope right now. I've attached a file of what appear to be eggs. I'm not seeing the traditional redbugs, but I am seeing A LOT of translucent globular shaped things that move VERY fast across the surface of the acro. They do appear to be flat, but I don't know if I've ever seen flatworms move this fast. They are so small that Even zoomed in the most I could on the scope, then 2x with the phone, and digitially zoomed I cannot show them, but that is partly because of them being transparent.

I know that this isn't a lot to go off of. At this point I'm thinking I should treat for redbugs and flatworms simultaneously. I think the browning out is perhaps a function of high phosphates. I'll be checking my RODI water tomorrow before to make sure its not unusually high in phos.

Again, any thoughts are HIGHLY appreciated.

 

[Deep]

How old is your tank? What lights are you running and have you measured par ? Browning could be low light. Your Nitrates are at zero and you have only 3 fish. How often do you feed ? I am not sure about the bugs and that could be another issue, but you said your softies and mushrooms were not doing well as well ?

 

[homer1475]

0 nutrients and brown corals means get the nutrients up to at least a detectable level, and increase the light.

The fact your softies are not doing well either would lead me to believe your nutrient may well actually be 0, or being used up by the algae before the corals can uptake any.

Why the decrease in fish? Only when I added more fish, did my system actually stable out.

 

[Neuratox]

0 nutrients and brown corals means get the nutrients up to at least a detectable level, and increase the light.

The fact your softies are not doing well either would lead me to believe your nutrient may well actually be 0, or being used up by the algae before the corals can uptake any.

Why the decrease in fish? Only when I added more fish, did my system actually stable out.

The tank is 2 years old almost to the day,

How old is your tank? What lights are you running and have you measured par ? Browning could be low light. Your Nitrates are at zero and you have only 3 fish. How often do you feed ? I am not sure about the bugs and that could be another issue, but you said your softies and mushrooms were not doing well as well ?

The take is 2 years old almost to the day, I've never measured par however the acropora are 8 in from the surface and I have 2 AI primes sitting directly above them while two marine orbit pros are running the length of the tank one in the front and one in the back. The acropora have been doing incredibly well especially in the last few months. I think that lighting could be improved however this tank is getting torn down and shifting into a new one. That's also the reason that my fish have decreased is because I am slowly transitioning them over to the new tank as it ages. The new tank is nowhere near stable enough to support acropora and I suspect not even the LPS yet. Furthermore the new tank is also in the ugly faze.

I think that perhaps my interpretation of the softies was inaccurate and likely due to me freaking out initially. None of them seem to be displaying any signs of stress any longer nor are my LPS such as my torch, frog spawn, grammer, etc although my duncans are displaying a browner color.

Is it possible that low nitrates could cause tissue loss at the edges?

Thanks for the input It's been a really stressful week

 

[Neuratox]

0 nutrients and brown corals means get the nutrients up to at least a detectable level, and increase the light.

The fact your softies are not doing well either would lead me to believe your nutrient may well actually be 0, or being used up by the algae before the corals can uptake any.

Why the decrease in fish? Only when I added more fish, did my system actually stable out.

Sorry it looks like I inadvertently responded to two of you simultaneously. I'm not so worried about the browning out right now these are being transferred into a new tank in a few months. What really concerns me is the tissue loss at the leading edge of the coral

 

[Deep]

Sorry it looks like I inadvertently responded to two of you simultaneously. I'm not so worried about the browning out right now these are being transferred into a new tank in a few months. What really concerns me is the tissue loss at the leading edge of the coral

Sounds like this problem coincides with your move to the new tank ( especially with the fishes), so I would guess it is probably the nutrients.

 

[Neuratox]

Sounds like this problem coincides with your move to the new tank ( especially with the fishes), so I would guess it is probably the nutrients.

Thanks I really appreciate this. I'm certainly going to focus on dropping the phosphate. I'll also try to start doing a couple of small water changes throughout the week rather than once a week.
I've also got some cheato that I can add to the system. Hopefully that will help out some

 

[homer1475]

He's not saying to lower nutrients,but rather to raise them. 0 nitrates is not good, and .1 po4 is certainly within range. I would not lower phosphates, or even worry about them, but add nitrate to detectable levels.

 

[Neuratox]

He's not saying to lower nutrients,but rather to raise them. 0 nitrates is not good, and .1 po4 is certainly within range. I would not lower phosphates, or even worry about them, but add nitrate to detectable levels.

Homer, thanks for correcting that, I misunderstood. I'll start feeding more to provide a higher nitrate level.

 

[homer1475]

The problem with feeding more, is your going to increase phosphates along with nitrates. Your phosphates are already at the top end of the scale.

I would be looking into adding just nitrates. Something like potassium nitrate you mix yourself, or a ready made solution like brightwells neo-nitro