0 Nitrate + 0 Phosphate = Hair Algae?

johnnyphish

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Tank is about a year old, 75 gal display, 95 total. Had a hair algae outbreak for the last month. Nitrates and phosphates are zero, or darn close.

According to ChatGPT, my rock may be "leaching" nutrients bc they are too low, and directly feeding the hair algae. So it's recommended solution is to counterintuitively increase my nitrates and phosphates from zero to low, along with manual removal, cleanup crew, etc.

Thoughts?
 

Reefin' Steve

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Tank is about a year old, 75 gal display, 95 total. Had a hair algae outbreak for the last month. Nitrates and phosphates are zero, or darn close.

According to ChatGPT, my rock may be "leaching" nutrients bc they are too low, and directly feeding the hair algae. So it's recommended solution is to counterintuitively increase my nitrates and phosphates from zero to low, along with manual removal, cleanup crew, etc.

Thoughts?
What are you testing with?
 

Hallowhead

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It makes perfect sense, you need to balance the chemistry between the rock and the water column and remain consistent for the phosphate from rock to enter water and be removed mechanically.

I'd dose slow and measure phosphate daily until it's measurable and then continue dosing and avoid water changes for a bit
 

bgray98

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Your hair algae is consuming your po4. Bare bottom tank or sand? Also what rocks? New dry or live rock?
 
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johnnyphish

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Your hair algae is consuming your po4. Bare bottom tank or sand? Also what rocks? New dry or live rock?
Crushed coral bed. Rocks are mostly 1 year old live rock, with a few much older pieces. Many months with no hair algae...
 

slingfox

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It is very possible that parameters are zero because the hair algae is eating them up to grow. Manual removal and increased size of CUC are advisable. You should also check nutrient import and export. Many new reefers feed their tanks too much. At least that is what I did during my first year in the hobby.
 
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johnnyphish

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It is very possible that parameters are zero because the hair algae is eating them up to grow. Manual removal and increased size of CUC are advisable. You should also check nutrient import and export. Many new reefers feed their tanks too much. At least that is what I did during my first year in the hobby.
Yeah I imagine the hair algae is gobbling up the nutrients, so that's why I wanted to check the intuition of increasing my nitrates and phosphates.

CUC? I tend to underfeed, if anything.
 
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Randy Holmes-Farley

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Tank is about a year old, 75 gal display, 95 total. Had a hair algae outbreak for the last month. Nitrates and phosphates are zero, or darn close.

According to ChatGPT, my rock may be "leaching" nutrients bc they are too low, and directly feeding the hair algae. So it's recommended solution is to counterintuitively increase my nitrates and phosphates from zero to low, along with manual removal, cleanup crew, etc.

Thoughts?

Unbelievably stupid AI answer. It makes zero sense. It is NEVER going to decrease nutrients anywhere in a reef tank (such as the surface of rocks) to add those same nutrients elsewhere.
 

Hallowhead

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Unbelievably stupid AI answer. It makes zero sense. It is NEVER going to decrease nutrients anywhere in a reef tank (such as the surface of rocks) to add those same nutrients elsewhere.
I will say, I have had awful GHA outbreak with 0ppm tested via icp and salifert and dosing phosphate has cut my GHA by maybe 70% over 3 weeks.

I don't think AI is saying that it directly removes phosphate but the rock and water column are chemically imbalanced and that by having levels of phosphate in the water column will help mechanical filtration remove that as well as the rock releasing stored phosphate.

Additionally dosing phosphate as caused my chaeto to explode and in return remove more phosphate from water column that the rocks release. Now listen everything I just said could be totally crap but it's working for me !
 

Randy Holmes-Farley

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What the ai said is simply wrong. It chemically cannot happen as the ai states. Your paraphrasing of its hypothesis is also something that cannot happen. Adding phosphate to the water NEVER can help phosphate be released from rock surfaces.

There can be many real explanations for your observation, as well as coincidence. Among the real explanations are the addition of phosphate spurring growth of competitors for space or for trace elements or for N, all of which may reduce a specific algae. The chaeto growth would also remove trace elements and N, and may be the cause here.
 

Hallowhead

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What the ai said is simply wrong. It chemically cannot happen as the ai states. Your paraphrasing of its hypothesis is also something that cannot happen. Adding phosphate to the water NEVER can help phosphate be released from rock surfaces.

There can be many real explanations for your observation, as well as coincidence. Among the real explanations are the addition of phosphate spurring growth of competitors for space or for trace elements or for N, all of which may reduce a specific algae. The chaeto growth would also remove trace elements and N, and may be the cause here.
So then could my phosphates really have just been 0 and adding phosphates helped my chaeto grow to our compete the GHA ? I've been fighting GHA for probably 5 months and doing weekly water changes and as soon as I stopped weekly water changes and starting dosing phosphates is when my GHA stopped spreading and started getting translucent and overall receding. Corals started popping a bit more and my chaeto grew.

I am totally conflicted because it's working
 

Randy Holmes-Farley

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It is certainly possible the algae growing in rocks gets phosphate that is releasing from the rocks, and that local concentration can easily be higher, temporarily, than the level in the bulk water. Before long, however, they will equilibrate. That process cannot be sustained long term.

.
Yes, to your question on competition with the chaeto. Competition for a trace element (also supported by stopping water changes) may have hurt the algae.
 

Hallowhead

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It is certainly possible the algae growing in rocks gets phosphate that is releasing from the rocks, and that local concentration can easily be higher, temporarily, than the level in the bulk water. Before long, however, they will equilibrate. That process cannot be sustained long term.

.
Yes, to your question on competition with the chaeto. Competition for a trace element (also supported by stopping water changes) may have hurt the algae.
So do you recommend continuing no water changes and dosing phosphate ?
 

Randy Holmes-Farley

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So do you recommend continuing no water changes and dosing phosphate ?

I recommend a bigger clean up crew for algae problems, rather than trying to limit N, P, or trace elements, since those same issues can impact corals negatively.
 

Hallowhead

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I recommend a bigger clean up crew for algae problems, rather than trying to limit N, P, or trace elements, since those same issues can impact corals negatively.
Every time I add snails they die. I'll spare you AIs reasoning for that one. However, no snails survive in my tank outside of the GHA there is really nothing to graze on. I have 3 urchins that mow the GHA down but they can't keep up with the larger stalks. The GHA is not growing back where the urchins have been since dosing phosphates and stopping water changes
 

ReefGeezer

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Not all Tangs will graze on hair algae. Bristletooth Tangs are best for that. Rabbitfish like maybe a Foxface are great algae eaters. Sea Urchins can help a lot but can also eat coralline, move insecure rocks, and stick small corals to themselves. Some Sea Hares can eliminate algae quickly but can also ink the tank if they get upset.

Personally, if the outbreak is not too bad, I'd remove it manually, scrub the rock with a toothbrush, and use a Turkey Baster to keep the rocks clear of detritus.
 

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