Corals dying slowly please help!

[Eagle aquatics315]

Hello everyone been a while since I have posted because everything has been fine up until the last 2 months. I have a 125 gallon mixed reef tank (1 year old) and I cannot for the life of me figure out why my corals are dying slowly, it is also a low nutrient tank. ALL of my parameters are were I like them and are posted below, they have not changed in months, I have SPS LPS and softies and most of them are either dying slowly or fading out. I have lost almost all of my SPS and some of my LPS like frogspawn, chalices and candy cane corals are slowly receding. ALL of my fish are totally fine and I have none that target coral and my inverts are also totally fine. I have not touched the lighting in a year, I run kessils and a zetlight 6500. Coraline is growing good and I use RODI water also and it reads 0TDS. I have well water also so there couldn't be chlorine escaping through the filter I don't think. I do have an infestation of red planaria flatworms in my refugium but I have never seen any in the tank and have dipped corals and nothing has come off of them, I also use Red sea blue bucket salt. I cant figure this out and it has me extremely frustrated!! IF anyone has any ideas please let me know THANKS!!
Parameters:
Temperature: 79F
Salinity: 1.025 (refractometer)
Phosphate: 0ppm (Hanna checker ppm)
Nitrate: 5-10ppm (salifert)
Alkalinity: 9.0 (Hanna checker)
Calcium: 425 (salifert)
Magnesium: 1320 (aquaforest)
pH: 7.7 (salifert)
Ammonia: 0
Nitrite: 0
RO water reads 0 tds but that's the only other thing I question?? No nutrients in it but can there be other things that can leach past the filters?

 

[AngryMike2016]

I'd start with getting those phosphates to register.

 

[Scurvy]

Has PO4 been zero for a long time? Alk looks a bit high with zero phosphates. Would probably be better off towards the 7.5 range in an ULNS.

I lost a lot of Euphylia after bottoming out phosphates for an extended period in an older setup.

 

[Eagle aquatics315]

I'd start with getting those phosphates to register.

I might try that, Thing is though I have always ran the phosphates at 0 with fantastic results.

 

[AngryMike2016]

Yeah, but it isn't going to last long term; ulns is really walking on the razor's edge. Get some seachem flourish phosphorous.

 

[rock_lobster]

Low phosphate is a definite proven coral killer Over time.

 

[Eagle aquatics315]

Has PO4 been zero for a long time? Alk looks a bit high with zero phosphates. Would probably be better off towards the 7.5 range in an ULNS.

I lost a lot of Euphylia after bottoming out phosphates for an extended period in an older setup.

Interesting Im gonna try raising them a little, what range do you recommend running when it comes to phosphates? That could be it I suppose because i really started worrying when LPS started dying. I have been running 0 phosphates for about 6 months maybe.

 

[Eagle aquatics315]

Low phosphate is a definite proven coral killer Over time.

Never knew that, I always thought it was good to have them near 0 because I have seen it a lot on some BRS videos, interesting.

 

[Eagle aquatics315]

Yeah, but it isn't going to last long term; ulns is really walking on the razor's edge. Get some seachem flourish phosphorous.

What does that do?

 

[AngryMike2016]

It just raises phosphates. Designed for planted freshwater tanks, but is perfectly fine for a reef. I have been using it to successfully raise my phosphates.

 

[IslandLifeReef]

Before you dose anything, what are you using for nutrient control. Any phosguard or GFO? If so, I would get rid of that first.

I agree with @AngryMike2016 that ULNS are walking the razors edge. Alk is high for ULNS, but I don't think that would harm the LPS, could be wrong though.

Have you checked your PAR? Just because the light has been running for a year and you like it doesn't mean that you haven't been slowly starving your corals.

 

[Eagle aquatics315]

It just raises phosphates. Designed for planted freshwater tanks, but is perfectly fine for a reef. I have been using it to successfully raise my phosphates.

Im gonna check that out thanks!!

 

[IslandLifeReef]

What Hanna checker are you using to measure the PO4, the LR or the ULR. The margin of error on the LR checker is 0.04, so if using that checker, your PO4 could be anywhere from 0.00-0.04. PO4 in the range of 0.03-0.1 is considered good by most.

 

[Eagle aquatics315]

Before you dose anything, what are you using for nutrient control. Any phosguard or GFO? If so, I would get rid of that first.

I agree with @AngryMike2016 that ULNS are walking the razors edge. Alk is high for ULNS, but I don't think that would harm the LPS, could be wrong though.

Have you checked your PAR? Just because the light has been running for a year and you like it doesn't mean that you haven't been slowly starving your corals.

I use GFO every now and then If i detect phosphates TBH. I took the last batch of it out a couple weeks ago. I alaso have a refugium sucking up nutrients pretty quick. I have not checked par cause I dont have a meter, but I have always ran the kessils at 60-70% and the same goes for the zetlight.

 

[Pete_the_Puma]

Agree with lowering ALK to near 7.0

 

[Eagle aquatics315]

What Hanna checker are you using to measure the PO4, the LR or the ULR. The margin of error on the LR checker is 0.04, so if using that checker, your PO4 could be anywhere from 0.00-0.04. PO4 in the range of 0.03-0.1 is considered good by most.

I use the LR checker, thats why I though seeing 0 was good because that means it is probably around .04 which is were I thought was perfect.

 

[IslandLifeReef]

I use GFO every now and then If i detect phosphates TBH. I took the last batch of it out a couple weeks ago. I alaso have a refugium sucking up nutrients pretty quick. I have not checked par cause I dont have a meter, but I have always ran the kessils at 60-70% and the same goes for the zetlight.

Take half of whatever you are running in your refugium out first and see if that helps.

 

[Eagle aquatics315]

Agree with lowering ALK to near 7.0

Im gonna do that

 

[Eagle aquatics315]

Take half of whatever you are running in your refugium out first and see if that helps.

Alright I was gonna do that anyway because a lot of my chaeto is infested with stupid flatworms

 

[IslandLifeReef]

I use the LR checker, thats why I though seeing 0 was good because that means it is probably around .04 which is were I thought was perfect.

I see your thought process, but it could also mean 0.00. Especially if you added GFO when you did detect PO4. That probably did strip it to 0.00.

You can dose, just be careful with it. I like trying to stay away from chemical fixes if I can. That's just my method.