Hi,
Sorry
@Seabass , been very busy. Changed jobs recently.
Things went downhill fairly quick since my last post. Lost a few coral. I am still not sure what caused this to be honest.
I lost 3 antheas

all three had the same symptoms. Stopped swimming - remained on a spot with fairly heavy breathing. Each took about 2 weeks to pass away when symptoms started. When the 1st one showed symptoms, I did feed medicated foods to treat internal parasites and infections, but did not help at all.
The one I bought to replace the initial one that died, seems fine. I added this one after that so it's not something she brought into the tank. Considering a lawnmower blenny to help me with my algae issue.
Nutrients are under control again. Slowly brought PO4 and NO3 down. I achieved this by increasing nopox dosing, large water changes and at some point dosing lanthanum. Something here that sunk in on this topic relates to the effectiveness of a water change is not determine by how much you change but by how much you take out at a time - doing a 100 liter Water change means nothing if you take out 20 liters at a time as this amounts to a reduction of parameters/elements at a very low effective rate. If memory serves when changing a 160 (representing about 69% of my tank volume) liter on my tank with me siphoning out 20 liters at a time resulted in a reduction of pollutants/elements at about 40%. The long and the short of it, when doing a water change try and match the input and output in 1 go.
Cheato for some reason no longer survive in my system. I added a large ball of cheato 2 weeks ago. This has shrunk to the size of a golf ball.
I am planning to get a ICP test done in the near future. Not sure if there are some pollutants or heavy metals in the water that caused the problem.
The last thing I investigated were pumps. All I noted here was the my reactor was offline for a few weeks due to the pump being clogged and dirty. Cleaned this and it's running like a champ again. Did note the shaft if completely broken and waiting for a replacement pump - the pump still works but gets stuck sometimes.
I'll post some pics as soon as I have some time to take nice pics of the chaos - record to see how things recover.