bleachin/fading/dieing Water test results in. What to do?

Over the last 6 months I have experienced bleaching or fading on my candy cane corals, hammer corals, and green star polyps and my zoas are melting and disappearing . I lost two different types of bubble corals also. Over the past 2 weeks three 7 year old clown fish died within 3 weeks, an extra large monticap died completely, and large colony of pulsating xenia has began deteriorating. Initially when I converted from vho's to t5's 12 months ago everything was brightly colored and crisp, but for the last 6 months everything seems like it is fading or bleaching more and more. For the most part everything else is doing well and growing. I have had my 80 gallon cylinder tank setup for 5 years. I have a standard 30 gallon sump tank with a Tunze DOC Protein Skimmer 9011. I have (6) 24" 24 watt t5 bulbs that are 12 months old ( 2 mid day and 4 actinic + ) . The 2 middays run from 9 till 7 and the 4 actinic+ run from 11 till 6. I also have blue led moon lights that run from 12 at night till 5 in the morning. All lights are about 10 inches from surface, but tanks is 20 inches deep. All corals that are bleaching are 10-20 inches below the water surface. I do 20% water changes per month with rodi water. I use bulk reefs 2 part alk/cal and solutions on dosing pumps and manually add their mag solution as needed.The only things I see are as follows: I switched from instant ocean about 12 months ago to marine enterprises intnl "crystal sea". Should I change back to Instant Ocean? I do not run carbon, gfo, filtersocks/floss etc. on my return water in the sump etc.. Just a protein skimmer. Do I need to add these things to my setup? I change my 3 stage ro/di water filters once a year, so it is hard for me to believe the rodi top off/water change water is the issue, but I am open to suggestions.
Temp 79-80 Salinity 1.23-1.25 My tanks is mostly LPS and soft corals (leathers, zoas, xenias, brains, colt ,hammer, frogspawn, galaxea, monticap, etc.) I have 3 clown fish and a watchman goby and feed them rods original food every 3-5 days. Although I have always had a grounding probe I found stray voltage about a month ago and fixed that, but it has not changed any of these problems. Could my lights be worn out and cause such dramatic fading in 6-12 months? Could I be running the lights too long?
Can you connect the dots between the test results and all the negative things happening in my tank? What should I do to bring the silca, molybdenum, strontium, and iodine down to acceptable levels?
Ammonia (NH3-4) Good=0.000
Nitrite (NO2)Good=0.005
Nitrate (NO3)Good=0.6
Phosphate (PO4)Good=0.01
Silica (SiO2-3) High=0.6
Potassium (K)Good=403
Calcium (Ca)Low=229
Molybdenum (Mo) High=0.2
Strontium (Sr)High=12.3
Magnesium (Mg)Good=1175
Iodine (I ̄)High=0.14
Copper (Cu++) Good=0.02
Alkalinity (meq/L)Good=2.80

 

Im gonna vote for the calcium levels being almost half of what they should be for the coral. As for the fish, idk...

you say your dosing 2 part... are you doing that right? because if you mess that mix up, man it can go south quick!

also i didnt see a Ph reading anywhere... whats that at?

 

ph 8.1 Been using the 2 part for 10 months without issue, but have let the calcium go low over the past 2 months from neglecting. My fauslt, but that should not cause fish to die and fading and melting of zoas , xenia etc.

 

Welcome to 3reef.

So this tank is 5 years old or more?

Have you disturbed the sand bed at all?

I would go back to IO, even though there is no rhythm or reason for why some tanks take a dive after changing salt mixes.

And wow your ca is low.

 

yes 5 years plus, have not disturbed the sand bed, but I do have a pistol shrimp with watchman goby that does alot of sand moving on a daily basis, but he is 2 years old and has been busy the whole time. My calcium has just dived off in the last 2 months because of my neglect, but for the past 12 months it has stayed 400-420 . The calcium dive does not explain the 3 fish dieing, xenia, and monticap dieing and fading of all the corals though?

 

maybe not the fish but the coral, im gonna say its a high probability that it is man. Calcium is needed for them to grow and survive, a drastic swing especially one so dramatic, could easily have been why. I mean i dont know for 100% but i have a suspicion it is.

The fish may have died natural causes for all we know, the 2 may not be related incidents.

 

I agree the calcium is an issue get it back up to 400-420 at 50ppm per day max. Bump up your Mg to 1280 or so. Dose Mg at 100ppm per day max.

The calcium does not explain the fish, it may have been their time or related to the coral die off. Xenia is so touch and go that it is hard to figure it's issue. The cap the Ca is definitely the cause. Hard corals are affected when Ca drops below 360. The fading could come from the Ca drop. I would move your lights up to 30" above the sand. And cut back to 4 bulbs in you do not see improvement in a month or so. You may want to consider changing bulbs also.

 

I would suspect the copper is taking it's toll. 0.02 is not good. In NSW, the concentration is only 0.0009, so your reading is several thousand times higher than normal.

Composition of seawater