Bleached tips and top side of SPS

[bishoptf]

I've been doing this for a few years, 4 to be exact and I have multiple tanks. One of my tanks I thought I had things dialed in but summer was busy and things were neglected water change wise ( I dose All for reef) nitrate and phosphate crept up. I increased my DIY nopox amount to try to bring down the nitrate (mid 40's) I was also using Phosguard to bring down phosphate levels, currently at .2 but I also adjust my lights and I think this is what did it. This is a shallow nano tank and even and I have a meter and after increasing I was in the 2-300 par range at the tops of the rocks (30g long, shallow tank) but I am not sure what irritated the SPS, almost all of them show issues with the tips and tops of branches that bleached so I lean towards to much light to fast etc. I never spiked my alk that I am aware of, I was running a little high alk wise for me @ 8.5dkh, normally like to be 7.7-8.0 range.

I am still trying to learn what my tank is telling me and would just like to know what most likely I did. I have raised my lights and lowered them, par level is lower and I guess I will just have to see how many pieces I lose now but thought I would ask and try to learn so I can not repeat it in the future.

Attached is a pic, is dark but makes it easier to see where tips and top of branches parts bleached with algae growing on it.

 

[subodhs]

I wish I could say I know what I'm telling you, but my experience has been that high alk and high nutrients cause acros to lose their tips, which get replaced by algae. A low alk causes the base to RTN/STN up. Just from my anecdotal experience, not something I have learnt with any science behind it.

 

[PocketGoose]

I've had tips bleach out in the past with alk swinging up (doesn't necessarily have to be a "spike"). Sounds like you've made a few changes at once though, sometimes that will make the issue hard to discern.

The light increase could have something to do with it too, do you know the PAR before you made the adjustment?

For future reference, I would make one change at a time. That way in the event something goes wrong, you can have a better idea of what the root cause may be.

 

[Formulator]

high alk and high nutrients cause acros to lose their tips

I’ve heard and experienced the opposite. High alk (faster growth) requires higher nutrient levels to keep up with growth, so low nutrients at high alk causes burnt tips. This is why ULN systems are typically run at lower alk.

 

[Formulator]

For future reference, I would make one change at a time. That way in the event something goes wrong, you can have a better idea of what the root cause may be.

This is great advice and something I always advocate for as well. We are keeping complex ecosystems here and practicing good scientific method is key to long term success. Isolate your variables!

 

[Dburr1014]

Lou Ekos slide, bullet point 1

 

[subodhs]

I’ve heard and experienced the opposite. High alk (faster growth) requires higher nutrient levels to keep up with growth, so low nutrients at high alk causes burnt tips. This is why ULN systems are typically run at lower alk.

I agree with you. I guess what I meant was a higher Alk swing from the normal kills the tips. And higher nutrients for growth (in case of ULNS SPS usually still means PO4 <0.1 ppm. Anything more than that inhibits the growth. The sweet spot is PO4 between 0.03-0.07 ppm.

 

[bishoptf]

Yeah not running a ULNS, my nitrate was around 40ppm and phosphate was .2ppm (it was actually up to .6ppm before I started taking it down). Alk had crept up to 8.5 but it was not a spike etc. My phosphate was quite high and I had been pulling that back down, so maybe pulling phosphate down to quickly plus the lights. I am really not sure but I know it only affected parts that are pointing up, shaded areas or the undersides did not bleach.

I'm just trying to understand what it was that caused it so I can learn and not make the same mistake.

 

[bishoptf]

I've had tips bleach out in the past with alk swinging up (doesn't necessarily have to be a "spike"). Sounds like you've made a few changes at once though, sometimes that will make the issue hard to discern.

The light increase could have something to do with it too, do you know the PAR before you made the adjustment?

For future reference, I would make one change at a time. That way in the event something goes wrong, you can have a better idea of what the root cause may be.

Eh Ive been doing this for awhile now, I know about making to many changes etc. I have 2 other nano SPS tanks, I just never have seen this exact thing before. I've seen STN/RTN etc but nothing like this. Its easy to say one change and I time but thats easier said that done. Going to do some larger water changes and get my numbers where I want them and then start coasting again and see what survives. I still think it was high light but I think its a combination of high light and something else. Hopefully things can recover and stop the regression.