SPS hate me. Looking for flow suggestions

[W1ngz]

For the tl;dr types, yes it's long, but I hope you hang in there. I've tried to get info up front to avoid pages of Q&A.

I've been struggling with keeping SPS happy once they make it to their final spot on the upper levels of my rock. I've gone through about 8 different types from a basic green slimer to a red dragon, and they've all died off. Encrusting montis and a cap survives, but growth is slow. Any acro will slowly decline over a couple of weeks until the STN sets in, and eventually I'm left with a brown and white peg. I'm reasonably comfortable in the idea that my flow is no good across the top. More on flow down below, after I go through parameters and lighting.

The pic below is about a year old, but gives a clearer view of my rock than anything recent. Pardon the GSP and xenia, it was all banished months ago.
-----------------------------------------------------
Requisite numbers, testing at least once a week here are my trends and ranges which have all been stable.

Ammonia 0.001 (yes, two zeros after the decimal, seneye)
Ca ~440-450 (salifert)
Alk ~7.8-8.0 (Hanna)
Mg 1470 (Salifert)
NO3 ~5 (Salifert)
PO4 ~0.08-0.10 (Hanna ULR)
pH 7.95-8.1, it will hit 8.2 on days when I'm home with the windows open.
Temp is a consistent 25.3-25.5C (77-78F)
SG is 1.026, done on a refractometer that gets calibrated every time I take it out of the box, with 35ppt solution that is never more than a year old.

The only change to these was a 3 week window late March to early April where I ramped down my alk from 9ish towards 8ish, thinking that was a possible cause. It wasn't, the next 3 acros I tried all did the same thing.

They do fine on a frag rack mounted at about the same height as the rock peak, on the right side pane where they get some reasonable par (seneye says about 180-200 at mid-day peak), and reasonable flow from the rear mounted powerheads deflecting up the glass. All have some decent polyp extension, until they get moved to the rocks about a week later. The light at the peak of the rock is only moderately higher than the rack, hitting around 220-230 at peak light. Given that, I don't think I have a light problem, or a water problem. Maybe an acclimation problem, so if I do another batch of small cheap acros, I may try and leave them on the rack for 2-3 weeks instead of just 1.

Lighting is an aquatic life hybrid with a blue plus and coral plus in each segment, and an A360WE in the middle at about 70%. The kessil comes on minimum (12%) and 100% blue at 7AM, then ramps up from from 9AM to noon to 70% and with 40% whites, then ramps down back down to 20% with 100% blue from 1PM to 5PM. From 5PM to 9PM it ramps down from 20% to minimum, and goes out at 9:30.
The t5s come on at 11AM and go out at 7PM.

For flow, there are two Tunze 6025s on the back, shooting forward. In the back right corner along the back wall and just catching the top edge of the rock, is a Koralia 1150. It's a really finicky placement and I can't ever seem to get it quite right, either it's too much flow blowing the flesh off the SPS, or too little and they STN. I need some suggestions on how to get some reasonable, consistent flow across the top, with very little space to do so. This is a 90cube, so across and front to back is 30". So far the only plan I've got is:

Gradually increase the kessil intensity to try and get the par near or above 250 at the top of the rock.
Leave the Tunzes firing towards the front
Move the koralia 1150 back a little to keep the flow behind the rock (there's 3-4" of space between the rock and the glass).
Add a nano powerhead up high on the right side, directed towards the edge of the topmost shelf. I'm thinking a Koralia 425. Anything stronger would just blow the corals apart given the short distance. I'm not sure how a nano powerhead would hold on 3/8ths glass.

 

[RMS18]

How long will a acro live on the frag rack? I'd test this out if you have. If it also dies then it's not a flow issue. I'd like to see a video of the flow, add some food so we can see how fast the flow is. Something else maybe causing the flesh to come off making you think your flow is to high.

 

[W1ngz]

I'll see about trying to get some video. Not sure why I didn't consider that before, but recording while I move an airline to the intake of each powerhead wouldn't be a bad idea so I can watch it and see where all the movement is.

There's a fresh batch of guinea-pig frags on the rack now, where they've been since last Tuesday. I'll see how long they last, or at least until I see them encrusting the base a little more.

 

[Crustaceon]

If my math is correct, your tank turnover is around 17x. IMO, you probably want to be over 30x for most sps. If I don’t see little polyps swishing every so often, I assume they’re not getting enough flow. Keep in mind if a coral isn’t getting enough flow, it can’t properly utilize nutrients or minerals in the water. Basically it can starve, which is something we see in STN from the base up. For reference, I’m running 45x turnover on my 55g with two jebao slw-20’s (1/2 power) and it seems pretty easy going in there flow-wise. 17x turnover in my tank would be stagnant water. The rest of your parameters look pretty good, so I’d start with adding another pump to increase flow or upgrading.

 

[RMS18]

I'll see about trying to get some video. Not sure why I didn't consider that before, but recording while I move an airline to the intake of each powerhead wouldn't be a bad idea so I can watch it and see where all the movement is.

There's a fresh batch of guinea-pig frags on the rack now, where they've been since last Tuesday. I'll see how long they last, or at least until I see them encrusting the base a little more.

It takes a lot to blow the flesh off of sps. I'm not familiar with your powerheads in person. My sps frags mounted get blasted with flow from 2 3k gyres, some 8 inches from the gyre. When I had issues with stn it was due to inconsistency with nutrients and alkalinity. Frag would bleach out within 2-3 weeks.

 

[W1ngz]

I don't really buy into those guideline numbers, especially on a mixed tank where the requirements down low can be vastly different from what's up high. That being said. I think I'm closer to 30x turnover.
Tunze 6025 = 740gph (x2)
koralia 1150
740+740+1150 = 2630. On a 90gal gal tank so 2630/90= 29.2x overall flow inside the tank.

Given that, I think I have enough flow, it's just in the wrong place and not enough of it is happening across the top of the rock. No?

 

[AZMSGT]

salinity? Never mind, I missed it. Unless you just added it and I’m not loosing my mind.
Nitrates at 5 are low.

 

[W1ngz]

salinity?

SG is 1.026, done on a refractometer that gets calibrated every time I take it out of the box, with 35ppt solution that is never more than a year old.

Nitrates at 5 are low.

Where would you have them? Everything I've seen in the last 2-3 years puts the overall consensus for nitrates at ~5ppm with PO4 lower than 0.1 unless running unusually high alk. I don't consider 8ish dkh to be unusually high.

 

[W1ngz]

salinity? Never mind, I missed it. Unless you just added it and I’m not loosing my mind.
Nitrates at 5 are low.

No no, I added it after your question, your mind is (probably) fine.

 

[AZMSGT]

Nitrates at 10-20 seem to do better. Not likely your issue just the only thing that caught my eye.

 

[W1ngz]

Nitrates at 10-20 seem to do better. Not likely your issue just the only thing that caught my eye.

I think I'm ok at 5ish. Honestly it's that ambiguous pink that could be 5 or 10. If the current batch of cheap frags does ok for several weeks on the frag rack, I'll have eliminated any question of water parameters.

One of the frags had a bit of leftover encrustation on the plug, which I left in the rack. It's since encrusted almost the whole plug, has fantastic PE every day, and is, I think is starting to grow upwards in the middle. That alone seems to suggest the lighting and water itself is fine. Especially if I can produce a whole new frag just from a 1/4" of leftover crust.

Short of any other suggestions, I think I'm going to try my plan for a small amount of broad flow directed right across the top. The koralia nano 425 will do that, I think.

 

[Beardo]

Looking at your parameters they all look great. I prefer the lower alk you are running now to the higher level you ran before. Nutrients look good to. I think a target of 5 for nitrates is fine, As long as there are some you should be good.

I have run kessil/T-5 hybrid for years and been really happy with them. The first thing that caught my attention was your peak lighting period is very short compared to mine. If I'm reading it correctly, you reach your peak at noon then begin ramping back down at 1:00PM. My peak intensity in comparison is from noon to 7:00PM. You could also run a higher percentage on your light. I have a 270 and run an 8 bulb sunpower and 6 a360we and run an intensity of 75% currently on the kessils and have been as high as 95%. And in previous tank with 2 t-5s in front and back ran 85% intensity with a long peak. Never measured par though so can't compare that
Not saying this is killing your acros but may be contributing so slow growth on your montis.
As far as light acclimation, I personally don't think that's an issue. More often than not, I glue my frags straight to the rock I want them on and don't have any issues.

In the flow department, I would think the flow bouncing off the front glass is moving water across the top of the rock structure. Is it possible to angle the powerheads inwards slightly? maybe get alittle cross flow?

One option to increase flow though would be a gyre type pump that moves water across the top of the tank in a pulse mode.

Nice tank though, I have always liked cubes (have a 50 cube as well.)

 

[Bacon505]

That’s a lot of writing with just one photo. Do you have any photo of the sps? What they look like before and dying process.

 

[Victor_C3]

If I don’t see little polyps swishing every so often, I assume they’re not getting enough flow.

Excellent point, that’s what I’ve always looked at to ensure there is enough flow.

For me, with the above in mind, flow has never been a problem. I always called it a “light roll”, but your word works for it too.

 

[jda]

Are you growing coralline? Is there a lot of biodiversity in your tank?

Some rocks look purple and some are pure white, so do not know if they are epoxy coated in purple.

Nothing in your write up looks suspicious. Perhaps just more time or a small order of real live rock from the ocean might help. Some tanks started with man man, dry or dead rock can take several years to act like other tanks. See if any of this rings true to your experience:

Revisiting my Elos tank after 18 months | Reef Builders | The Reef and Saltwater Aquarium Blog

Sometimes we just aren’t as smart as we think we are. I am using the “royal we” as I know I am definitely not as smart as I think I am a lot of the tie, especially when it comes to this hobby.

reefbuilders.com

 

[W1ngz]

Some rocks look purple and some are pure white, so do not know if they are epoxy coated in purple.

Like I mention in my somewhat long explanation, that photo is a year old taken just a few days after a tank swap. Most of the white is newly exposed rock due to the new layout of the tank.

Here's a few taken just now. The white looking one is actually a very pale green. You can see the polyp extension on the leftover crust from the near dead green slimer frag plug. Not so good on the macro shots but if you look carefully you can see all the polyps on the current batch on the rack.

 

[Plunder]

For the tl;dr types, yes it's long, but I hope you hang in there. I've tried to get info up front to avoid pages of Q&A.

I've been struggling with keeping SPS happy once they make it to their final spot on the upper levels of my rock. I've gone through about 8 different types from a basic green slimer to a red dragon, and they've all died off. Encrusting montis and a cap survives, but growth is slow. Any acro will slowly decline over a couple of weeks until the STN sets in, and eventually I'm left with a brown and white peg. I'm reasonably comfortable in the idea that my flow is no good across the top. More on flow down below, after I go through parameters and lighting.

The pic below is about a year old, but gives a clearer view of my rock than anything recent. Pardon the GSP and xenia, it was all banished months ago.
-----------------------------------------------------
Requisite numbers, testing at least once a week here are my trends and ranges which have all been stable.

Ammonia 0.001 (yes, two zeros after the decimal, seneye)
Ca ~440-450 (salifert)
Alk ~7.8-8.0 (Hanna)
Mg 1470 (Salifert)
NO3 ~5 (Salifert)
PO4 ~0.08-0.10 (Hanna ULR)
pH 7.95-8.1, it will hit 8.2 on days when I'm home with the windows open.
Temp is a consistent 25.3-25.5C (77-78F)
SG is 1.026, done on a refractometer that gets calibrated every time I take it out of the box, with 35ppt solution that is never more than a year old.

The only change to these was a 3 week window late March to early April where I ramped down my alk from 9ish towards 8ish, thinking that was a possible cause. It wasn't, the next 3 acros I tried all did the same thing.

They do fine on a frag rack mounted at about the same height as the rock peak, on the right side pane where they get some reasonable par (seneye says about 180-200 at mid-day peak), and reasonable flow from the rear mounted powerheads deflecting up the glass. All have some decent polyp extension, until they get moved to the rocks about a week later. The light at the peak of the rock is only moderately higher than the rack, hitting around 220-230 at peak light. Given that, I don't think I have a light problem, or a water problem. Maybe an acclimation problem, so if I do another batch of small cheap acros, I may try and leave them on the rack for 2-3 weeks instead of just 1.

Lighting is an aquatic life hybrid with a blue plus and coral plus in each segment, and an A360WE in the middle at about 70%. The kessil comes on minimum (12%) and 100% blue at 7AM, then ramps up from from 9AM to noon to 70% and with 40% whites, then ramps down back down to 20% with 100% blue from 1PM to 5PM. From 5PM to 9PM it ramps down from 20% to minimum, and goes out at 9:30.
The t5s come on at 11AM and go out at 7PM.

For flow, there are two Tunze 6025s on the back, shooting forward. In the back right corner along the back wall and just catching the top edge of the rock, is a Koralia 1150. It's a really finicky placement and I can't ever seem to get it quite right, either it's too much flow blowing the flesh off the SPS, or too little and they STN. I need some suggestions on how to get some reasonable, consistent flow across the top, with very little space to do so. This is a 90cube, so across and front to back is 30". So far the only plan I've got is:

Gradually increase the kessil intensity to try and get the par near or above 250 at the top of the rock.
Leave the Tunzes firing towards the front
Move the koralia 1150 back a little to keep the flow behind the rock (there's 3-4" of space between the rock and the glass).
Add a nano powerhead up high on the right side, directed towards the edge of the topmost shelf. I'm thinking a Koralia 425. Anything stronger would just blow the corals apart given the short distance. I'm not sure how a nano powerhead would hold on 3/8ths glass.

Try boosting you Alk to 10.

 

[W1ngz]

The first thing that caught my attention was your peak lighting period is very short

Thanks for reading right down to the nitty gritty details. I've been toying with the idea of upping the intensity another 10% and extending that peak time to a couple of hours. I'll plan a schedule to start moving that along over a couple of weeks.

 

[W1ngz]

Try boosting you Alk to 10.

I don't think that's the issue. With stable parameters and questions around the subtleties of flow and lighting, changing the alk now will destabilize the whole dosing balance as well as the alk/po4/no3 balance.

 

[Bacon505]

That back wall has a lot of coraline, as much as it look nice it will consume a lot of your trace elements. Competing with your corals. Its hard to say what is really affecting your sps but have you test for metal in your system? Heavy metal can purge the algae out of the corals lightening the colors