Chronic STN on Base of SPS Corals

[AgentSPS]

Folks-

Did a cursory search for threads and didn't find much so apologies if this is redundant. I think this issue is fairly pervasive so hopefully we can get some reliable feedback here to help out those affected.

In the last year, despite diligent efforts to maintain NSW levels (Triton testing), I have been experiencing chronic STN on the base of many of my SPS. Before the flow trolls chime in, I got plenty of flow. I have also heard people saying that there needs to be sufficient nitrate and phosphate. While very low levels, I have detectable levels of both. I get light algae growth on the glass over 2-3 days and very healthy growth of chaeto in fuge.

My Li levels are very high and rising but from all that I have read, Lithium is considered very low toxicity and its not really known what affects, if any, on coral.

Including results of April testing:

 

[AgentSPS]

I target salinity of around 1.024 and Alk of 10dkh. Alk seems to want to dip down to between 8-9 within 5-7 days of supplementing sodium bicarbonate. Pretty much doing on weekly basis. Turned up the Ca reactor recently to try and stabilize

 

[Piper27]

Have you tried leaving alk at 8? Are you using a new alk source?

 

[AgentSPS]

Have you tried leaving alk at 8? Are you using a new alk source?

Its my understanding that low alk can cause recession at the base whereas high burns tips. Given all the trouble I have had with RTN at the base, I figured higher alk might rule that out.

Would actually be easier for me to maintain at 8.

Curious what your thinking is around this.

 

[jda]

Are we talking colonies or frags?

Look lighting and shadowing. Do you have a light that is chronically prone to shadowing issues?

Lithium is no issue. It is likely from your salt mix. I would not worry about it.

 

[AgentSPS]

Mostly colonies but there have been frags too. Frags seemed to be more STN but maybe just because there is not as much tissue to RTN away...if that makes any sense.

Shadowing not an issue...the recession is fairly evenly distributed over lit and shaded

 

[jda]

It is mostly likely a light issue. The death does not just always happen in the dark areas.

I keep my nitrate around .1 and phosphate around .005 to .01 and my acropora thrive - lower N and P are not your issue... this does not cause death.

 

[Piper27]

Its my understanding that low alk can cause recession at the base whereas high burns tips. Given all the trouble I have had with RTN at the base, I figured higher alk might rule that out.

Would actually be easier for me to maintain at 8.

Curious what your thinking is around this.

I was wondering where you have normally kept you alk at? Always high? Some tanks just do well on the low end and the rules don't always apply to every tank in the same way.
It would be very helpful to see pictures, even if it looks like standard tissue recession one of us might notice something.
What lights are you using? I should have asked this first and I could guess since jda chimed in that its leds?

 

[AgentSPS]

I was wondering where you have normally kept you alk at? Always high? Some tanks just do well on the low end and the rules don't always apply to every tank in the same way.
It would be very helpful to see pictures, even if it looks like standard tissue recession one of us might notice something.
What lights are you using? I should have asked this first and I could guess since jda chimed in that its leds?

Yeah tried to keep it around 10 for nearly a year now. I will see if I can capture some photos.

I am using Radions. I tried one of their new diffusers on my LPS tank but doesnt seem to be much different to me other than less noticeable shimmering.

 

[DesertReefT4r]

Keep you alk at 8 imo thats perfect. Its a bonus if its easy to maintain that level. Pics help a lot. Could be many things: constant alk swings from dosing to keep it high, flow which all you said was plenty, lighting too little or too much or constant changing of color and intensity ie "playing" with the light, shadowing, several water quality issues, pests like red bugs aefw nudis and black bugs. Please share more info tank size, flow, filtration, full water test, what gen Radions how many how high over the tank, bioload/livestock, dry roxk or live rock, how old is the tank?

 

[AgentSPS]

Keep you alk at 8 imo thats perfect. Its a bonus if its easy to maintain that level. Pics help a lot. Could be many things: constant alk swings from dosing to keep it high, flow which all you said was plenty, lighting too little or too much or constant changing of color and intensity ie "playing" with the light, shadowing, several water quality issues, pests like red bugs aefw nudis and black bugs. Please share more info tank size, flow, filtration, full water test, what gen Radions how many how high over the tank, bioload/livestock, dry roxk or live rock, how old is the tank?

I will stop adjusting Alk and leave it at 8dkh

Tank:
300 gal 72x40x24

Flow:

• 2 x MP60
• 1 x Tunze 6105
• 1 x Tunze 6055

Lighting:

• 3 x Radion XR30 (gen 3 I believe)
• 1 x Radion XR15 (gen 4)

• Set it some time ago and don't meddle
• Most of the SPS are between 12-14" from surface with lights maybe 18" above surface for spread coverage

Filtration:

• Skims Leopard Cone Skimmer w/ DC pump (I believe rated for 700+ gals)
• 30 gal fuge to brim with chaeto
• GFO (~10 oz) fluidized
• Perigen (~500 ml) fluidized

Stock:

• Combination of live rock and dried branch (formerly live from prev system) Maybe 150-200lbs?
• Tank has been up for about 4 years now
• Only sand is a 14" x 9" x 4" deep wrasse sleeping quarters
  
• Tank is moderately stocked with fish load
• 15-20 SPS colonies and 10 frags

 

[AgentSPS]

 

[Piper27]

How do you get away with a 40 inch wide tank and 3.5 led lights? Do you have all the rocks in the middle with lots of swim room? This is off topic but I am just curious. Love the dimensions of the tank.

 

[AgentSPS]

How do you get away with a 40 inch wide tank and 3.5 led lights? Do you have all the rocks in the middle with lots of swim room? This is off topic but I am just curious. Love the dimensions of the tank.

Yes so the rock work runs mostly along the rear of the tank with the ends sweeping towards the front. Think crescent shape if viewed from the top. Lots of open swim room in the front of the tank. There is good overlap of the lighting at the height I run the lights. Very little shading and none where it matters.

 

[DesertReefT4r]

Yeah you dont have near enough light for that tank size and the are mounted pretty high up. I would have about 6 XR30 Pros on a tank that long wide and deep at about 8-10" off the water. Having that high does increase spread/coverage but PAR dropps off very quickly. I bet you have less than 150 PAR reaching most of your sps coral. Flow looks decent imo at least by you powerhead list. Tank is mature so that's a plus. I would concentrate on just keeping water parameters stable, and adding more light. Dont chase numbers so much just stable and balanced. We all know what water parameters are needed for reef tanks so I wont post that.

 

[AgentSPS]

Yeah you dont have near enough light for that tank size and the are mounted pretty high up. I would have about 6 XR30 Pros on a tank that long wide and deep at about 8-10" off the water. Having that high does increase spread/coverage but PAR dropps off very quickly. I bet you have less than 150 PAR reaching most of your sps coral. Flow looks decent imo at least by you powerhead list. Tank is mature so that's a plus. I would concentrate on just keeping water parameters stable, and adding more light. Dont chase numbers so much just stable and balanced. We all know what water parameters are needed for reef tanks so I wont post that.

Measured tonight. Lights are 13" off water and coral 7" under water line.

 

[scottbeyer101]

I second the increased lighting. I have 1/2 your volume and nearly as much light (3 X Hydra 26) 9" off water line. I borrowed LFS's par meter and was surprised how little PAR was reaching even the middle depths.

As you mentioned the STN at the base of the acros does raise the question of AEFWs and/or red/black bugs. Wrasses are said to manage those buggers pretty well, but it is worth inspecting closely. You'll have to pull an affected frag or colony out of the tank and view under light and powerful magnifying glass to be sure. Hopefully not your problem, but if it is there is much well written advice on next steps.

Beautiful tank btw. Good luck.

 

[AgentSPS]

I second the increased lighting. I have 1/2 your volume and nearly as much light (3 X Hydra 26) 9" off water line. I borrowed LFS's par meter and was surprised how little PAR was reaching even the middle depths.

As you mentioned the STN at the base of the acros does raise the question of AEFWs and/or red/black bugs. Wrasses are said to manage those buggers pretty well, but it is worth inspecting closely. You'll have to pull an affected frag or colony out of the tank and view under light and powerful magnifying glass to be sure. Hopefully not your problem, but if it is there is much well written advice on next steps.

Beautiful tank btw. Good luck.

Def not AEFW or red/black bugs. I have had experience with both in prev tank and this has no resemblance.

Light is plausible. I just have really good coloration which made me think it was not lighting. I will try and locate a par meter to test

 

[robbous]

It is mostly likely a light issue. The death does not just always happen in the dark areas.

I keep my nitrate around .1 and phosphate around .005 to .01 and my acropora thrive - lower N and P are not your issue... this does not cause death.

I'd like to know how you keep them at these levels? When they rise above these limits do you change out the media? And when changing out the media how do you get it back to these exact same levels?

 

[jda]

I do not use any media.

2-3 inches of sand for denitrification. Lots of real phosphate-free live rock from the pacific for phosphate swapping/buffering (along with the sand). Water changes, large skimmers and chaeto/dragon[flame/tongue] fuge for export. ...and about a year if patience for all of this to start working correctly. My tank handles this naturally, on it's own. I set up every tank this way and it just works. I just started one 4 months ago...and working through the ugly phases right now, but I will let the tank sort this out and I will not intervene with any media... the N needs to stay a bit high so that anoxic bacteria can grow to consume it...and the P needs to stay a bit high so that the fuge continues to grow as the snails and fish take care of the algae in the display. I just started to get coralline everywhere, so this is a good step.

Using dry rock will not make this possible for a long time (if ever) since it is bound full of phosphate already, is not always porous and usually bound with caked organics. Using media will inhibit the tank from doing this on it's own. Large, good skimmers in large sumps can really help too... but the current trend is on pre-made sumps with small chambers and small skimmers with pumps in them where even a 20 year old EuroReef will produce more than one of these.

Basic Berlin with good maintenance gives people all that they need to run a successful tank, but I do get that patience is hard to come by anymore and BRS cannot make a video about running a tank with stuff that they do not really sell.

Twenty years ago, the only high nutrient tanks were those that were neglected... and there plenty of them. Hobbyists who cared had great tanks, but most did not get cute and try and not change water or deviate from what works. High nutrient tanks that had caring owners only started to pop up when bare bottom got big, then GFO and then dry rock. This is a relatively new phenonomen in reef keeping.