Bleaching and browning

[T-J]

On top of what's already been suggested, maybe send out for an ATI ICP test? The nice thing about ATI is that you send in a sample of your RODI water too. So you'll find out if there is anything in your source water.

 

[Alan M]

On top of what's already been suggested, maybe send out for an ATI ICP test? The nice thing about ATI is that you send in a sample of your RODI water too. So you'll find out if there is anything in your source water.

I sent one in a little over a month ago. Everything looked ok other than a some metals, but I was told it wasn’t to big of an issue. I have another ati icp on the way to Germany right now.

 

[Alan M]

Alright, related to Alkalinity levels in your tank (alk swings will absolutely cause some coral to RTN), nothing you have shared leads me to believe there is any reason your alk should be rising without your dosing something, and you are not. I think you should solve this before you do anything else. Your fritz salt should mix to ~8.5 dKH, and the fact that your water is 9-10, even after a water change, is a problem.

At super low pH, calcium carbonate structures could dissolve, which will raise alk, but your pH is well above where that would happen. And your fish would all likely be dead anyway in that case. Artificial rock that hasn't fully cured can also raise alk. This MAY be a factor in your case, but it should have resolved fairly quickly. It certainly shouldn't be an issue now. Another thing that can cause alk to increase is a precipitous drop in nitrates. Like huge. If you went from 80 to 20, that 50ppm drop can increase alk by about 5ppm (!). So if your nitrate has been dropping rapidly over the past several weeks, that could cause a steady increase in alk. The only other thing that could be causing it is the quality of your top-off water, the additives you're using to condition the water (chlorine removes, etc.), or medicines you may be using in the tank to treat fish. If you're using RO water, check the TDS of that and make sure it is 0. If none of that is the issue, you're going to need to keep looking.

Ultimately, you really need to solve the alk issue before you look at anything else.

Thanks for the detailed response. No big nitrate drops. Always steady around 5. I have well water so I don’t use conditioner. RO water is always at zero TDS. I burn through di resin quickly with my well water but have a 8 stage unit and keep a close eye on tds reading. I know this alk thing is an issue and as you say, it needs to get solved. Personally I’m just out of ideas. I’ve done so much reading on here and haven’t found a solution to it. Kinda baffling when everything is steady week to week but alk just keeps climbing.

 

[Jonify]

Thanks for the detailed response. No big nitrate drops. Always steady around 5. I have well water so I don’t use conditioner. RO water is always at zero TDS. I burn through di resin quickly with my well water but have a 8 stage unit and keep a close eye on tds reading. I know this alk thing is an issue and as you say, it needs to get solved. Personally I’m just out of ideas. I’ve done so much reading on here and haven’t found a solution to it. Kinda baffling when everything is steady week to week but alk just keeps climbing.

I know it's frustrating. But there has to be a reason, which means there must be a solution Check in with @Randy Holmes-Farley in his chemistry forum and bring the issue up there. He might have some insights. Also, I edited my post ... 50ppm nitrate drop would be a 5dKH increase (not ppm...typo). I know you knew what I was talking about, but don't wanna get flamed by others. THEY KNOW WHO THEY ARE.

 

[Alan M]

I know it's frustrating. But there has to be a reason, which means there must be a solution Check in with @Randy Holmes-Farley in his chemistry forum and bring the issue up there. He might have some insights. Also, I edited my post ... 50ppm nitrate drop would be a 5dKH drop (not a 5ppm alk drop...typo. Alk usually measured in dKH not ppm). I know you knew what I was talking about, but don't wanna get flamed by others. THEY KNOW WHO THEY ARE.

I will do that. Thank you for taking the time. Much appreciated.