Phosphate E and Alkalinity swing?

[Novicereefer]

Hi,

I think Phosphate E by Brightwell is a great product. It does what it says, but every time I dose it, I notice my sensitive corals (Acros and Torches) look upset the next day - loss color, polyps not as extended and in some cases just flat out die. This has been a consistent thing for a few weeks now and everything else is stable. I tested my Alk which has been around 7.8 (Hanna checker) then a few days later it was 6.8 and after a water change it's 7.4. Is this normal? Am I missing something? Is running a bag of GFO in my sump and Refugium a better option? I've upped my kalkwasser dosing to slowly bring it back up though. So we'll see

Update - just tested 2 min ago - it's 6.8 after it being 7.4 on Tuesday. I mean the only corals I see growing is my Setosa and Chalice so it can't be them taking it all up.

 

[Randy Holmes-Farley Verified Community Expert]

Are you tracking phosphate? What is it after dosing?

Lanthanum does have the potential to reduce alk if overdosed.

 

[Novicereefer]

Yes. Started at.37 then dropped to.24 then dropped to.19 then to.08 then to.02. Then I stopped using it. This was over the course of a week. In that time I lost 3-4 torches and basically my Acros all bleached. It wasn't until I checked my alk and saw that it was really low compared to what I normally run it at

 

[Randy Holmes-Farley Verified Community Expert]

The coral negative response may be from phosphate drop itself.

 

[Justdrew]

Yes. Started at.37 then dropped to.24 then dropped to.19 then to.08 then to.02. Then I stopped using it. This was over the course of a week. In that time I lost 3-4 torches and basically my Acros all bleached. It wasn't until I checked my alk and saw that it was really low compared to what I normally run it at

I would vote for the drop being too fast. Also think it went too low.

 

[Tcook]

An old thread but interesting. I had been using Phosphate E at the full dose for 3-4 weeks lowering phosphate from 0.25 down to 0.02. Some lps contraction. Alkalinity when from 9 down to 5.8 which was shocking. Started dosing more alkalinity and my Hanna checker has had 3 readings over the past 36 hours of 4.6 dkh. It seems hard to believe and wonder if the Phosphate E is binding one of the test reagents. Been over a week since last using the Phosphate E.

 

[Randy Holmes-Farley Verified Community Expert]

An old thread but interesting. I had been using Phosphate E at the full dose for 3-4 weeks lowering phosphate from 0.25 down to 0.02. Some lps contraction. Alkalinity when from 9 down to 5.8 which was shocking. Started dosing more alkalinity and my Hanna checker has had 3 readings over the past 36 hours of 4.6 dkh. It seems hard to believe and wonder if the Phosphate E is binding one of the test reagents. Been over a week since last using the Phosphate E.

Excessive lanthanum will precipitate lanthanum carbonate and/or oxide, thereby lowering alkalinity. I cannot see a testing issues caused by lanthanum in the test.

That said, this effect is much higher than anyone else has reported that I have seen, so unless you overdosed lanthanum quite a lot, other sorts of testing errors may be at play.

 

[Tcook]

Excessive lanthanum will precipitate lanthanum carbonate and/or oxide, thereby lowering alkalinity. I cannot see a testing issues caused by lanthanum in the test.

That said, this effect is much higher than anyone else has reported that I have seen, so unless you overdosed lanthanum quite a lot, other sorts of testing errors may be at play.

I ran a Salifert alkalinity test last night and got the same result, 4.6. Hard to believe but must be correct. I still get some haze on the front glass of the tank so there may still be some free lanthanum present over a week later. I plan to do a large water change today and test the freshly mixed water an tank after the change. My calcium is pegged at 500+ so must be correct for alkalinity?

 

[Randy Holmes-Farley Verified Community Expert]

I ran a Salifert alkalinity test last night and got the same result, 4.6. Hard to believe but must be correct. I still get some haze on the front glass of the tank so there may still be some free lanthanum present over a week later. I plan to do a large water change today and test the freshly mixed water an tank after the change. My calcium is pegged at 500+ so must be correct for alkalinity?

Why must the alk test be correct? There are plenty of threads on issues with Hanna reagents.

What does the Hanna say for alk in the new salt water?

This is from this morning:

https://www.reef2reef.com/threads/hanna-checker-reagent-quality.1150351/

"As do alkalinity, I use it biweekly to check and see if I have drift in my Trident ACM. This last week, it gave a reading almost 3 points lower than my ACM. So, I pulled out my salifert kit and tested with it, and it was with 0.2 of the ACM."

 

[Tcook]

Why must the alk test be correct? There are plenty of threads on issues with Hanna reagents.

What does the Hanna say for alk in the new salt water?

This is from this morning:

https://www.reef2reef.com/threads/hanna-checker-reagent-quality.1150351/

"As do alkalinity, I use it biweekly to check and see if I have drift in my Trident ACM. This last week, it gave a reading almost 3 points lower than my ACM. So, I pulled out my salifert kit and tested with it, and it was with 0.2 of the ACM."

I saw that thread and have had issues with Hanna in the past but worse with the Trident too. Both my Hanna and Salifert show 4.6 in my tank. I guess it is possible both could be wrong but both are brand new reagents. Couple days ago the LFS used Salifert and got a reading of 5.8. Will check the new salt water once it is made tonight.

 

[Randy Holmes-Farley Verified Community Expert]

I saw that thread and have had issues with Hanna in the past but worse with the Trident too. Both my Hanna and Salifert show 4.6 in my tank. I guess it is possible both could be wrong but both are brand new reagents. Couple days ago the LFS used Salifert and got a reading of 5.8. Will check the new salt water once it is made tonight.

Are you dosing alk, and if by automated delivery, you sure it has not run out or clogged or something?

 

[Tcook]

Are you dosing alk, and if by automated delivery, you sure it has not run out or clogged or something?

I am dosing your recipe (60 ml/day) and did find that the end of the tube was clogged twice over the past month and have been watching it closely since. I have also made 30 ml additions of the alkalinity twice a day and saw no change in the test numbers. Could I have that large of a deficit? The dosing tube may have been clogged for over 4 weeks prior to finding it. Tank is 120 gallons.