Help undo what I’ve done.

[Rcat]

I set up a 125g non-drilled tank 15 months ago. my nitrates hovered around 40ppm using red sea test kit and my phosphate around 1.6. Hanna checker. My fish and corals (lps and softies) were all healthy and growing. The more I read the more I was convinced that my levels were to high and I needed to lower them. 3 months ago I started with chemi blue and with weekly 20% water changes and monthly canister maintance I was able to lower to 34ppm and 1.1 respectively. 1 month ago I started dosing nopox at first 3ml a day and worked my way up to 5ml 2x a day. Nitrate and phosphate are not going down and in the last week I have lost two euphyllia and a Goni. The rest of my corals are loosing color and polyps are not extending as they were. currently running an FX4 canister and a Reef oct 2000 hob skimmer, 120lbs of rock.
My water parameters are:
Temp: 78.4
Sal: 1.026
Ph: 8.1
Ammonia: 0
Nitrite: 0
Nitrate: 34ppm
Phosphate 1.0
Dkh: 11
Calc: 410
Mag: 1310
What did I do or what am I missing.

 

[sfin52]

I set up a 125g non-drilled tank 15 months ago. my nitrates hovered around 40ppm using red sea test kit and my phosphate around 1.6. Hanna checker. My fish and corals (lps and softies) were all healthy and growing. The more I read the more I was convinced that my levels were to high and I needed to lower them. 3 months ago I started with chemi blue and with weekly 20% water changes and monthly canister maintance I was able to lower to 34ppm and 1.1 respectively. 1 month ago I started dosing nopox at first 3ml a day and worked my way up to 5ml 2x a day. Nitrate and phosphate are not going down and in the last week I have lost two euphyllia and a Goni. The rest of my corals are loosing color and polyps are not extending as they were. currently running an FX4 canister and a Reef oct 2000 hob skimmer, 120lbs of rock.
My water parameters are:
Temp: 78.4
Sal: 1.026
Ph: 8.1
Ammonia: 0
Nitrite: 0
Nitrate: 34ppm
Phosphate 1.0
Dkh: 11
Calc: 410
Mag: 1310
What did I do or what am I missing.

I would look at the dkh. That's high. Most like 8-10. Nitrates are not that bad and phosphates would be better a bit lower. Instead of nopox a refugium may be better.

 

[DEWreefing]

I have always believed in higher alk I run mine at 9.8 to 10 my nitrates are around 40 and my phosphates hang around .90 to 1. Your tank was doing fine try to remember most people start having issues when they try to change parameters. I run a full sps dominate tank and my growth and colors are great. Remember if it's not broke don't fix it. I would try to feed a little more to get your tank back to where it was. Also when you drop nutrients you need to bring down the alk as well.

 

[Retro Reefer]

Agree lowering your nutrients with that high of an Alk reading is probably what’s stressing your tank, I try to keep mine around 8 - 8.5 but because of some recent algae issues I dramatically cut back feedings and had to lower Alk to around 7 because everything started getting angry.

 

[Katrina71]

I'd try a fuge too. I'd drop it slowly. I'm not a fan of quick fixes.

 

[BeejReef]

Anyone correct me if I'm wrong, but NoPox kind of leans on the skimmer to remove the bacteria from the system. Not sure a HOB skimmer is going to do the job on a tank of that size.

I agree with others. A refugium is so easy. $25 grow lights on ebay all day. It might not drop you all the way, but it's slow and stable.

11 dkh is a little high, but if that's what you were running and doing well under, not sure I'd peg it as the main concern. What I've read though, is that corals become more sensitive to lighting when alk is high and N and P are low or drop rapidly.

Best of luck,
Sorry about your corals.

 

[Jon Fishman]

I am guessing under-skimming is a big issue here