What trace elements could cause my coral decline

[wasabi bean]

So i have always monitored my water parameters and they have remained fairly stable, my nitrates have always been quite high even with carbon dosing but my corals didn’t seem to mind (about 20ppm) recently i had ich and i had a phosphate spike getting the fish out, i then got this back down but my pavona between water changes looks really rough, is this just an effect of previous high phosphate or is there a trace element that is being used up very quickly after the water change?

 

[wasabi bean]

And also if my coraline algea is growing pretty quickly at this point why are my other corals looking so poor

 

[wasabi bean]

Here is the pavona

 

[Mr. Mojo Rising]

It could be anything really. How high was the phosphate?

The only way to know if trace elements are used up is with an icp test, its not something we can know.

If you can share some picture of the coral and the tank, share parameters, type of lighting and flow, and a bit of tank history, maybe someone can venture a guess, but there's not much info to go on right now.

 

[VintageReefer]

There is a lot beyond trace elements for coral health. Would need to know full tank parameters, history, lighting, flow, age of tank. Pictures of the tank and coral

 

[VintageReefer]

Can you add some white in so we can see better

 

[wasabi bean]

I

Can you add some white in so we can see better

sure can, the phosphate peaked to about 1ppm and i got it back down to 0.05ppm over a month and a half, here are parameters for the last couple months

18/1/25

• Kh 5.6
• Mg 1220
• 450
• Po4 0.2

02/02/25

• kh 6.4
• Ca 440

27/02/25

• No3 20
• Kh 7

07/03/25

Before WC

• po4 0.03 too low
• No3 20
• Kh 7.0
• Ca 430

After WC

• po4 0.08
• No3 16

28/05/25

No3 - 25

Mg -1200

Ca - 390

Kh - 9.8

Po4 - 1 high



11/06/25

No3 - 30

Mg - 1230

Ca - 380 low

Kh - 10.2

Po4 - 0.5 high



15/06/25

No3 - 20

Mg - 1210

Ca - 415

Kh - 11.2

Po4 - 0.5 high



28/06/25

No3 - 20

Kh - 9.9



4/07/25

No3 - 20

Po4 - 0.08

Kh - 9.3

Mg - 1290

Ca - 400

 

[VintageReefer]

Ok thank you

FYI my phosphate recently spiked to .8ish and I spent a few days lowering to .5
I’m typically .3-.5 and have had spikes to 1.0 before. It’s never caused an issue for me on corals. I’m not sure phosphate is the issue

 

[wasabi bean]

I

sure can, the phosphate peaked to about 1ppm and i got it back down to 0.05ppm over a month and a half, here are parameters for the last couple months

18/1/25

• Kh 5.6
• Mg 1220
• 450
• Po4 0.2

02/02/25

• kh 6.4
• Ca 440

27/02/25

• No3 20
• Kh 7

07/03/25

Before WC

• po4 0.03 too low
• No3 20
• Kh 7.0
• Ca 430

After WC

• po4 0.08
• No3 16

28/05/25

No3 - 25

Mg -1200

Ca - 390

Kh - 9.8

Po4 - 1 high



11/06/25

No3 - 30

Mg - 1230

Ca - 380 low

Kh - 10.2

Po4 - 0.5 high



15/06/25

No3 - 20

Mg - 1210

Ca - 415

Kh - 11.2

Po4 - 0.5 high



28/06/25

No3 - 20

Kh - 9.9



4/07/25

No3 - 20

Po4 - 0.08

Kh - 9.3

Mg - 1290

Ca - 400

Here is a picture under white light it was growing super well here and then in within a week all the flesh in the middle just receded and it has never really recovered

 

[VintageReefer]

I would guess the fluctuation in alkalinity is a factor. This really should stay as stable as possible. Little swings are ok but we are talking 8.3 to 8.5 and small ones like that

 

[wasabi bean]

I would guess the fluctuation in alkalinity is a factor. This really should stay as stable as possible. Little swings are ok but we are talking 8.3 to 8.5 and small ones like that

Yeah it was stable for a long time but with such rapid coral decline and no recovery the tanks uptake has varied a lot, im currently trying to figure this out by adjusting concentrations

 

[p1u5h13r4m24]

Ya that alk fluctuation is insane. Also the phos drop is really bad. One thing you need to keep in mind is some corals will take almost a month to show signs from a negative event that happens today. This is why it’s so important to stay stable and don’t panic to make adjustments. I’d say your two most important pararmeters
Would be dkh stay stable. Than phos. Keep it around .1-.3 also also, if you have high alkalinity like above 8dkh you must have higher nutrients such as 10-20 nitrate and .1-.3 phos for 10dkh

 

[VintageReefer]

Ya that alk fluctuation is insane. Also the phos drop is really bad. One thing you need to keep in mind is some corals will take almost a month to show signs from a negative event that happens today. This is why it’s so important to stay stable and don’t panic to make adjustments. I’d say your two most important pararmeters
Would be dkh stay stable. Than phos. Keep it around .1-.3 also also, if you have high alkalinity like above 8dkh you must have higher nutrients such as 10-20 nitrate and .1-.3 phos for 10dkh

This is correct. While I am not sure on the exact numbers, having high alkaline should be paired with higher phosphate and nitrate.

When these relationships are not proper, you get issues like skeleton growing faster that tissue. Not saying that’s what’s going on here, but numbers wide, things are all over the place

 

[p1u5h13r4m24]

Yes and I know that you will notice pale colors if the dkh/nutrient ratio is off. Overall coral health will be declined if not properly balanced

 

[Reginald Reefer III]

It's worse having no nutrients than elevated nutrients. Prolonged, bottomed out phosphate is tough to recover from once the corals start to starve and go downhill.

 

[VintageReefer]

Yeah it was stable for a long time but with such rapid coral decline and no recovery the tanks uptake has varied a lot, im currently trying to figure this out by adjusting concentrations

Easiest way to manually adjust dkh is baking soda and a calculator.

Stop dosing any alk products and get yourself to 8-8.5. Pick a number you want. I suggest 8.5. That’s the goal.

Then measure daily, same time each day. Figure out the daily drop.

Use this website.
https://reef.diesyst.com/chemcalc/chemcalc.html
Figure out how much baking soda is needed to increase your tank by .2 dkh

When tsnk drops from 8.5 to 8.3, add that amount of baking soda. Just stir it in a cup of rodi and pour in the sump

Measure next day. And repeat until you have a repeatable pattern. Such as: every 3 days I need to add 1 tsp baking soda

Right now your tank alkalinity is unstable and using complicated products will probably make things harder. Once you can identify the pattern and know the daily or weekly drop, then you can do the conversions and switch back to products. Or you can keep using baking soda. It’s cheap and easy. I ran my tank for years on it.

 

[wasabi bean]

I

Ya that alk fluctuation is insane. Also the phos drop is really bad. One thing you need to keep in mind is some corals will take almost a month to show signs from a negative event that happens today. This is why it’s so important to stay stable and don’t panic to make adjustments. I’d say your two most important pararmeters
Would be dkh stay stable. Than phos. Keep it around .1-.3 also also, if you have high alkalinity like above 8dkh you must have higher nutrients such as 10-20 nitrate and .1-.3 phos for 10dkh

never knew that, i always thought phosphate should be like 0.05ppm, maybe the bubble algae im having is due to low phosphate then

 

[p1u5h13r4m24]

I

Ya that alk fluctuation is insane. Also the phos drop is really bad. One thing you need to keep in mind is some corals will take almost a month to show signs from a negative event that happens today. This is why it’s so important to stay stable and don’t panic to make adjustments. I’d say your two most important pararmeters
Would be dkh stay stable. Than phos. Keep it around .1-.3 also also, if you have high alkalinity like above 8dkh you must have higher nutrients such as 10-20 nitrate and .1-.3 phos for 10dkh

never knew that, i always thought phosphate should be like 0.05ppm, maybe the bubble algae im having is due to low phosphate then

Yes this was the idea for a very long time and one of the reasons I failed for the first few years. The hobby has changed and we now realized that higher nutrients really aren’t that bad. It’s more about balance and being stable. You want clean water but not low nutrients if that makes sense. Less dissolved organic compound (DOC) but nutrients are the bottom of the food chain for all forms of life in your reef.

 

[wasabi bean]

Easiest way to manually adjust dkh is baking soda and a calculator.

Stop dosing any alk products and get yourself to 8-8.5. Pick a number you want. I suggest 8.5. That’s the goal.

Then measure daily, same time each day. Figure out the daily drop.

Use this website.
https://reef.diesyst.com/chemcalc/chemcalc.html
Figure out how much baking soda is needed to increase your tank by .2 dkh

When tsnk drops from 8.5 to 8.3, add that amount of baking soda. Just stir it in a cup of rodi and pour in the sump

Measure next day. And repeat until you have a repeatable pattern. Such as: every 3 days I need to add 1 tsp baking soda

Right now your tank alkalinity is unstable and using complicated products will probably make things harder. Once you can identify the pattern and know the daily or weekly drop, then you can do the conversions and switch back to products. Or you can keep using baking soda. It’s cheap and easy. I ran my tank for years on it.

So i have used bicarbonate of soda for a while, the tank used to take 34 grams per fortnight but i have reduced that since to about 23 grams and i am still adjusting

 

[wasabi bean]

Yes this was the idea for a very long time and one of the reasons I failed for the first few years. The hobby has changed and we now realized that higher nutrients really aren’t that bad. It’s more about balance and being stable. You want clean water but not low nutrients if that makes sense. Less dissolved organic compound (DOC) but nutrients are the bottom of the food chain for all forms of life in your reef.

Thanks, now i know the problem i can work on it, before i was just lost at what was wrong