Getting frustrated...coral bleaching

veselym · Nov 1, 2015

I have a 55G tank that has been up for almost 8 months and I didn't start adding coral until the 5 month mark

I have 2 AI Vega's 10' off the surface and around 47X turnover in the tank...I used BRS reef saver rock and am running a 20G sump with reef octopus NWB110

I have mostly LPS and a couple SPS pieces...SPS are 3 monti's, 1 tri color birdsnest, 1 digitata, 1 table acro, 1 ora borealis and a green birdsnest

I have multiple LPS expelling zoox and bleaching, my table acro/borealis and green birdsnest are brown (the ora borealis and acro are growing however). My red monti's are very pale and my zoas are only growing down

everything was doing fine up until a month ago when I started dosing potassium nitrate, I got my nitrate level up to .50 then my green birdsnest browned/bleached and now it seems everything is going down hill...lps not as open, some zoas not opening and can't figure out what is causing it

I thought I may have had a huge spike in P04 and did 9 10% WC's over a 2 week period but algae continues to grow on the glass...had cyano in sump and it has decreased by 85%

my lighting schedule has a 4 hour ramp and 5 hour max intensity at 29 white and 58 blue

parameters

ALK 8.8
CAl 420
Mag 1300
PH 7.9
Sal 1.025
Temp 79
N03 .50
P04 with Hannah 0.00 (have a little algae on glass)

MY alk has been stable for months, never swinging more than .3...I haven't messed with lighting or touched/moved any corals

I don't know what to do...thought about lowering light but browning in sps tells me not enough light or too many nutrients which I don't think I have. I have tested RODI and holding containers all reading 0.00 P04

twilliard · Nov 1, 2015

How about knowing for sure

veselym · Nov 1, 2015

I would but feel if I wait any longer then it could cause me to loose everything...I believe it could either be too little light or high P04, however it is very hard to tell based on minimal algae growth/chaeto not growing rapidly but LPS expelling/fading

I don't want to make a drastic change but yet I fell if I don't do something it will all die

billwill · Nov 1, 2015

Why are you dosing potassium nitrate? Unless you're running an ULN system, I find it hard to believe zero nitrates. I'd back off on dosing that.

veselym · Nov 1, 2015

I did stop dosing it after I noticed browning...I had zero nitrates before dosing and no algae growth

I had some corals respond very well, get richer in color and start growing but some things are not doing well like a birdsnest, some fruit loop zoanthids, 2 euphyllia and one monti

I have acans that are growing, candy canes that are splitting, both acro's are growing and gaining color

some stuff is growing and seems fine while others not so much

veselym · Nov 1, 2015

could it be possible that with the low percentages I am running along with adding a little nitrate caused the sps to build up zoox and LPS to expel it because of the excess nutrients with little PAR?

I don't want to light shock but have ran under 30% white for over a month...I am scared to bleach things but my gut is telling me to go up and my mind is saying don't due to Vega's being powerful

I just find it hard to believe that no more than 2ppm nitrate could cause serious browning or expelling of zoox...maybe under low PAR but I am not sure