cyano

ok so I seem to have an issue with receding tissue on LPS corals that I have kept for years successfully. I first started noticing these issues after I lost all my sps as I have unsuccessfully raised sps since installing my bio-pellet reactor I took it offline, cleaned it, and stowed it away. The problems persisted and I thought perhaps since some bryopsis has persisted and lived in my refugium that maybe it was a cause (plus since the fuge was extremely dirty since I was having a hard time getting a siphon to clean it) I also took it offline. The thought was that I was going to go back to the basics to a time when I was growing corals successfully and lower tech plus I had never had a algae problem or even detected nitrates in my previous set up. After taking both items off line I have noticed a bit of hair algae growing in the main display which I fully expected since the tank was relying more on the refugium and reactor than biological filtration in the main set up and sump.

I purchased a montipora cap frag as a coral I had a lot of success with in the past to try to use as a canary since they are fast growers and are very hardy in the right conditions. I have noticed that it is starting to show signs of new growth which is encouraging that I may be on the right track but I see no noticeable change in my lps flesh. I have started feeding my duncan a little more frequently to see if that helps but my branching hammer doesn't take food well (I have successfully fed it on occasions and witnessed food enter the mouth but the rest of the tank doesn't seem to like it) being that feeding of those corals is rarely successful or even heard of and me being successful without feeding it for 3 years I would rather not stress anything else out.

I was starting to think about what else could have changed from 3 years ago to now and I started to think about toxins leaching into the tank from somewhere. I have used to same buckets and before I would make RO water and top off the tank (before an ATO) and I would make salt water and usually do a change after about an hour of the water mixing. Well now I have an ATO so I usually make 10 gallons of top off water, one 5 gallon bucket with an aqualifter and a power head in it and one more 5 gallon bucket to add as needed to the first one. I also make 5 more gallons of water that mixes in a bucket with fresh salt for a period of about 24 hours before I do a weekly water change. I theorized that maybe over time the plastic in the buckets had started leeching harmful elements into the water that I have been adding to the tank. I did a little research and found people stating that plastics rated 1-5 were considered food grade with grade 2 being considered the best and grade 5 being questionable. Well the buckets I mostly use are old salt buckets which are a grade 5 and one other bucket that is used to store water being a grade 2. Not wanting to take any chances I have just purchased 3 more grade 2 buckets that I am filling with water as I type and will be taking my old buckets offline immediately to cover my bases.

So has anyone else experienced symptoms like these? If so did you ever find the cause?. All parameters are within range and all other livestock are fat and happy (not overfed though :P)

What type of plastic ratings do you use/recommend?

Any advice or help is greatly appreciated. It is very frustrating to be successful with certain corals for years and then feel like a failure. I have also taken my auto feeder offline so that no flake food it added to the aquarium.

I have also tested for stray voltage and found none as well as started dosing carbon in case there is something to absorb.