Phosphate Vs Acropora

[Reefahholic]

This is a very sensitive topic, but one that is very relevant and interesting to discuss if you keep a lot of Acropora.

Over the years I’ve seen our hobby shift from Zero nutrients, ULN, and today most run from ULN’s except the ZEOvit guys. I found out a long time ago that many Acro’s do not like ULN’s. They seem to do much better at higher phosphate levels or with a consistent food source available. I won’t debate how each reefer decides to feed his/her corals. Some of you guys/gals are brilliant when it comes to keeping a reef. You may have a large fish population giving the corals natural fertilizer or maybe you’re dosing organic carbon growing/feeding your bacterial population. Maybe you’re supplementing nitrogen and phosphorus and using strong diffuse lighting to keep the corals happy. You might even be spot feeding every single Acro at night with the flow off and soaking your food in amino’s vitamins, etc. LOL. Yes, we’re tried it all to make these corals grow!

What I would like to discuss is those who run higher nutrients vs lower nutrients.

I’ve seen corals thrive at both ends. Yes we’ve all heard that calcification rates slow down in higher nutrients, but I can’t say I’m completely sold on that yet. I’ve seen some amazing systems running at what most would consider very high levels. Of course it goes far beyond N&P, but at least we can measure these at home. I know we can measure total phosphorus with ICP, and also orthophosphates using a photometer. We can measure nitrate, but I do believe some nitrogen sources may not be detected, and some phosphorus sources are bound to the rock and sand, and who knows where else. @jda seems to be knowledgeable with some of that front-end vs back-end discussion and I enjoy listening to him and others like @Dr Balling @Dr. Farley even though I may not agree with everything I certainly listen and appreciate their opinions and knowledge.

We all have different opinions on what a good nutrient range should be. Opinions are great and we can have civil discussions! I’m in the camp that .03,.02.01 is getting low (for me personally), and it starts to make me nervous. I’ve lost some beautiful corals at those levels in newer systems that I believe I wouldn’t have lost had the levels (specifically phosphorus) been a little higher or if the tank was 3-4 yrs old. Maybe there wasn’t enough food available. Either way, I like to play it safe now, and prefer to stay north of about .06 ppm phosphate. I also don’t like my nitrates below 3 ppm. Lately I’ve been running much higher than I ever have trying to put to death some lingering Ostreopsis Dino’s. I’ve been keeping phosphate north of 0.3, and up to almost 0.5ppm. Sounds crazy to most I know. The first time I tried to let the Phosphate get up this high the tank browned out pretty significantly. I think I just got to the target a little too quickly. This time, I went even slower and took my time. I did experience some mild browning with a few corals, but much less significant than the previous time. It was also short lived. Within a week or two it was gone. Actually both events didn’t last very long. As long as you bring the level down they seem to recover fairly quickly. This problem wouldn’t be the case if you were at 0.5 and then went up to 0.4 within a few days. Lol. Both of my events took place at much gradual intervals. Over the course of weeks. I’m currently sitting at 0.365 ppm and the tank looks pretty darn good. Obviously the color isn’t as vivid as .05, but it’s not too far off.



I know several of you stick heads here run higher nutrients and I’m just wondering if you’ve experienced the same at higher phosphate levels and at what levels did you see browning or did you see any at all, because every system is different. Corals will adapt if the target is achieved gradually!

I think Richard Ross is a prime example of that. If I recall correctly he’s been up to 1-2 ppm PO4. Not 0.1-0.2, but yes….1.0-2.0 ppm with Acro’s and the corals look decent. Also, Sanjay was keeping his tank at 0.4 ppm PO4 and 50 ppm NO3 for a long time. Not that he targeted those numbers, but I believe he said the tank just kinda settled there. We all know Sanjay grows corals pretty fast. Although, I do remember him saying he saw faster growth when he decided to take the levels down a bit.


With that said, where are you at currently and have you had better success at higher or lower levels of Nitrate and Phosphate? By success I mean survival, growth, and color. If your coals are vivid, but your loosing 25 Tenuis each year, I’d probably not define that as success. Which corals have you noticed having issues with higher or lower levels? Post a few pics and let’s
dialogue.

Remember, we can all learn from one another and everybody has their own opinions or preferences for their own tank. We can be civil and disagree and it’s OK! I can tell you, this dry rock system I have just doesn’t like low phosphate (currently), and I just don’t know why. That will likely change later, but the tank simply does better right now if the PO4 is 0.12 ppm or higher. 0.45ish seems to be the limit. After that it will start to grow some GHA. Every system is different and what may work in one system may be hard to achieve in another.

Cheers!


Here we have a Garf Bonsai loving life in 0.36 PO4.

 

[billyocean]

I try to be around .06-.12 for phosphate but wouldn't worry about being higher at times. My hanna ULR read .02 and I got dinos about 4 months ago or so. I know it wasn't bottomed out as I dose phosphate on a doser. Being that I don't have a big fish load in my 125..I choose to dose phosphate to keep my levels up. Nitrate is hand dosed every so often to keep around 10-20ish. I don't run any filtration except for socks and rocks and occasionally some GAC .8 rox. I'm far from any expert on this subject but have found this works extremely well for my tank. Acros have great growth and great color. No set numbers really but a general range I like to be in.
Alk 8ish
Mag1400-1480ish
Cal 425-450ish

 

[Reefahholic]

I try to be around .06-.12 for phosphate but wouldn't worry about being higher at times. My hanna ULR read .02 and I got dinos about 4 months ago or so. I know it wasn't bottomed out as I dose phosphate on a doser. Being that I don't have a big fish load in my 125..I choose to dose phosphate to keep my levels up. Nitrate is hand dosed every so often to keep around 10-20ish. I don't run any filtration except for socks and rocks and occasionally some GAC .8 rox. I'm far from any expert on this subject but have found this works extremely well for my tank. Acros have great growth and great color. No set numbers really but a general range I like to be in.
Alk 8ish
Mag1400-1480ish
Cal 425-450ish

I’d say that is a great place to be. Thx for sharing!

 

[jda]

For some level set, there are some things about phosphate that most folks do not know.

Most people intermingle phosphate and phosphorous, but they are quite different. When reading literature or a post from somebody smart, P means phosphorous the building block and po4 means phosphate (ortho) the waste product.

Your corals don't care about phosphate. They need phosphorous, not phosphate. There are many, many sources of phosphorous in your tank. There are many kinds of organically bound phosphorous, many types of metaphosphate and phosphate in living organics. Bacteria and other microscopic living things have phosphorous and there is strong evidence that in mature tanks, these are very easily caught and assimilated in the slime coat with nearly 100% retention of all building blocks and energy.

We can only measure one kind of phosphate, which is orthophosphate. Even the Hannah which says phosphorous is the same test as the phosphate with a match calculation. We cannot measure or test for the many other different phosphorous sources.

There are papers and studies that show that coral (they mean true coral - stonies) prefer metaphosphate and organically bound phosphorous. There are studies about anemones also that say the same thing. None of them say that the corals cannot use phosphate, just that it is not preferred. Your fish produce all different kinds of phosphorous waste in different forms.

Phosphate is the leftover once all of the other forms or phosphorous break down. By accident, I found that metaphosphate takes about three days to fully break down into orthophosphate. There seems to be a window there where there is a good, available, preferred phosphorous source available for corals to use.

There is evidence in this hobby that metaphosphate is processed by corals differently than orthophosphate. Many folks have indicated that GFO has harmed their corals, yet LC has not. GFO binds many different kinds of phosphate (meta and ortho) whereas LC binds mostly ortho. When you use LC, you might be leaving metaphosphate behind for your corals to get phosphorous still while you lower orthophosphate levels. If this is true, then it is also evidence that corals do not use orthophosphate over metaphosphate, or at least can use them both.

Phosphorous is not energy. It is a building block of life. It is not used like sugar/carbs/OC for functioning. It is used to build new organic tissue. Surplus is surplus - you cannot use more than you can use kinda like having a dinner table with 100 lbs of food on it will not get you any more stuffed than 10 lbs. Dosing to raise phosphates to growth-limit dinos, diatoms or cyano is a different discussion that a surplus for coral use, so I will stay away from this since the thread is a battle-royale with Acropora. While energy and building blocks are all nutrients, it is best to separate the two in discussions - it is like saying that you plan to keep coral in your tank.

In the end, do not think that a single test of orthophosphate is an indication of the available phosphorous in your tank. It is likely that if you have value on a phosphate test kit, that indeed your tank is not limited at all.

I don't care where people keep their numbers. That is all up to them. My fuge and multiple skimmers keep my tank at 1-3 ppb, but it has gone up to 6-10 for short bursts when wierd things happened like when I tried to feed a large group of stupid anthias and I had to feed a ton more. My tank is not phosphorous limited with phosphate in this range - everything grows as fast as it does for anybody else.

 

[jda]

There was a thread a while back in the chemistry section about higher phosphate levels inhibiting calcification. It is pretty much true. However, it probably does not matter to most and might not matter at all depending on what you keep. There was some evidence that some corals barely slowed down at all but also that others completely stopped growing.

There is something zen about just figuring out what levels you want to keep, how much you want to spend and how hard that you want to work and just get corals that work in this paradigm. If you want to keep any coral, any where at any time, then you will need to be more near seawater level of phosphate while always having a good amount of phosphorous in the tank.

 

[jda]

My last post on this for the night... probably. If you lowered backend po4 by cutting out food or import, then corals will likely be hurt. If you added lots of consumers like a fuge, more corals, etc. and did not up the import to match, corals likely will be hurt. You are also cutting back on the other preferred forms earlier in the chain if you cut back on import. If you just took po4 from the backend while still feeding a lot, then the tank will likely have plenty of available P and your corals will be fine.

 

[billyocean]

Thanks @jda

 

[Reefahholic]

Thanks for those comments and recommendations Jda. Always good to hear different perspectives. I wish somebody could develop that perfect Phosphorus product. I have a good one, but the problem is that it is too rich and feeds Dino’s with the corals. In a normal established system it would be fine, but my tank is still too young and the Dino’s capitalize on every mistake I make. The corals love it though. I really like the idea of bacteria loaded full of PO4 feeding the corals, but I’m not sure I’ve seen much of a difference from organic carbon dosing. Maybe a little better growth. Maybe I did it wrong. Either way, I’m always looking to crack that phosphorus code! I want to get the right form and amount into the coral, but I’m unsure of how to do that in the most effective way. I just got CoralFragZ secret phosphorus sauce about 6 months ago and still have tried it yet. That’s next on the list. He told me if I share it I’ll be put to death. So nobody ask me please.

 

[jda]

Unless the product is made fresh and on site, I don't know if you won't just end up with more breakdown over time and just have ortho in a bottle.

The fish are the best source of multiple kinds of phosphorous that I know of. If you are not fishless, just feeding those guys probably cannot be beaten.

You can buy metaphosphate in dry form, but I have no idea if they are good type or not. There are a bunch of different types. I guess the worst case is that they end up as ortho in a few days.

 

[Kasrift]

I typically ran phos really low, but I water changes with probiotic salt and don't have big dishes in my 32 gallon. I sat around .02-.04, with nitrates at 5-8.

However, I was trying to get rid of some bryopsis and doses Reef Flux. This jumped my phosphates (that and not dosing live phyto) to .36. I didn't have any losses, but it shocked me. I don't want to make fast changes, so it's been slowly dropping over the last two weeks about, at .19 as of yesterday's test. I was curious as to why .36 didn't kill off the acros, so interesting read on this thread. I had no idea others ran it so high.

 

[DangerDave]

Low nutrients has never performed well in my systems. When it comes to nutrients in my reef heavy in and heavy out is how I roll...

 

[billyocean]

I typically ran phos really low, but I water changes with probiotic salt and don't have big dishes in my 32 gallon. I sat around .02-.04, with nitrates at 5-8.

However, I was trying to get rid of some bryopsis and doses Reef Flux. This jumped my phosphates (that and not dosing live phyto) to .36. I didn't have any losses, but it shocked me. I don't want to make fast changes, so it's been slowly dropping over the last two weeks about, at .19 as of yesterday's test. I was curious as to why .36 didn't kill off the acros, so interesting read on this thread. I had no idea others ran it so high.

I would think it was just the phosphate bound in the algae that died

 

[Kasrift]

I would think it was just the phosphate bound in the algae that died

That is exactly what I think happened. Gives me heart palpitations to have my parameters so out of wack. Been testing twice daily, morning and night. So far things are doing fine.

 

[rtparty]

I don’t test for or care what my PO4 reads

 

[billyocean]

I don’t test for or care what my PO4 reads

Even if it's not old enough for adult books?

 

[jda]

I typically ran phos really low, but I water changes with probiotic salt and don't have big dishes in my 32 gallon. I sat around .02-.04, with nitrates at 5-8.

However, I was trying to get rid of some bryopsis and doses Reef Flux. This jumped my phosphates (that and not dosing live phyto) to .36. I didn't have any losses, but it shocked me. I don't want to make fast changes, so it's been slowly dropping over the last two weeks about, at .19 as of yesterday's test. I was curious as to why .36 didn't kill off the acros, so interesting read on this thread. I had no idea others ran it so high.

I would not expect relatively short term exposure to .36 to do anything of harm to most corals. Some of the most sensitive might suffer a bit. Some acropora won't care at all.

In my $1000 build thread, the ORA German Blue Digi would lose it's bright blue color if the po4 got above .15, or so. It still grew, but slower, and was kinda blue, but not as bright as it could be. When I would lower the po4, it would get super bright blue again. All of the other montis looked the same.

Purple Monster, Pink Panter, some planas and many other old-school acropora that have kinda dwindled in recent years mostly have done so because of a trend towards higher residual building blocks and also heavy-blue lighting. My PM pretty much slowed growth to nothing when po4 would be to even .10 or .15 - not stop, but very, very slow.

What makes this hard is that what seems like slow growth to me might be plenty fine for others. The same is true with color.

Your dead algae also quit consuming phosphorous in one of it's forms which allowed the breakdown and po4 to rise. Double whammy with dying algae release building blocks but also not consuming them anymore.

 

[jda]

Another thing about building blocks. They are necessary for all living things, but also are poisons at high levels. There is a sliding scale where they stop becoming useful, start to be a burden and then start to lead to death. This happens with coral, algae, humans and anything.

Some of you know about this when you have kept your nitrate and/or phosphates higher to limit dinos. You made their lives harder and/or even poisoned them by doing this.

Another example is that many inverts will not function as well with higher building block levels - mostly no3 compared to po4. They might still function, but not as well and eventually they can die. Urchins and snails at .01 po4 and .1 no3 mow down tons of algae, but they do not move as well or eat as much as these levels rise. Again, they can still do some work, so people who have never seen them function at peak form probably will never notice.

Every type of coral that I have ever kept has had different levels of sensitivity to elevated building blocks. One of my favorite Z&P is Gonzo's Space monsters, but these melt with higher no3 levels. Acropora are no different.

Coralline grows annoyingly fast with lower level building blocks. It is really annoying.

 

[rusgum]

This is a very sensitive topic, but one that is very relevant and interesting to discuss if you keep a lot of Acropora.

Over the years I’ve seen our hobby shift from Zero nutrients, ULN, and today most run from ULN’s except the ZEOvit guys. I found out a long time ago that many Acro’s do not like ULN’s. They seem to do much better at higher phosphate levels or with a consistent food source available. I won’t debate how each reefer decides to feed his/her corals. Some of you guys/gals are brilliant when it comes to keeping a reef. You may have a large fish population giving the corals natural fertilizer or maybe you’re dosing organic carbon growing/feeding your bacterial population. Maybe you’re supplementing nitrogen and phosphorus and using strong diffuse lighting to keep the corals happy. You might even be spot feeding every single Acro at night with the flow off and soaking your food in amino’s vitamins, etc. LOL. Yes, we’re tried it all to make these corals grow!

What I would like to discuss is those who run higher nutrients vs lower nutrients.

I’ve seen corals thrive at both ends. Yes we’ve all heard that calcification rates slow down in higher nutrients, but I can’t say I’m completely sold on that yet. I’ve seen some amazing systems running at what most would consider very high levels. Of course it goes far beyond N&P, but at least we can measure these at home. I know we can measure total phosphorus with ICP, and also orthophosphates using a photometer. We can measure nitrate, but I do believe some nitrogen sources may not be detected, and some phosphorus sources are bound to the rock and sand, and who knows where else. @jda seems to be knowledgeable with some of that front-end vs back-end discussion and I enjoy listening to him and others like @Dr Balling @Dr. Farley even though I may not agree with everything I certainly listen and appreciate their opinions and knowledge.

We all have different opinions on what a good nutrient range should be. Opinions are great and we can have civil discussions! I’m in the camp that .03,.02.01 is getting low (for me personally), and it starts to make me nervous. I’ve lost some beautiful corals at those levels in newer systems that I believe I wouldn’t have lost had the levels (specifically phosphorus) been a little higher or if the tank was 3-4 yrs old. Maybe there wasn’t enough food available. Either way, I like to play it safe now, and prefer to stay north of about .06 ppm phosphate. I also don’t like my nitrates below 3 ppm. Lately I’ve been running much higher than I ever have trying to put to death some lingering Ostreopsis Dino’s. I’ve been keeping phosphate north of 0.3, and up to almost 0.5ppm. Sounds crazy to most I know. The first time I tried to let the Phosphate get up this high the tank browned out pretty significantly. I think I just got to the target a little too quickly. This time, I went even slower and took my time. I did experience some mild browning with a few corals, but much less significant than the previous time. It was also short lived. Within a week or two it was gone. Actually both events didn’t last very long. As long as you bring the level down they seem to recover fairly quickly. This problem wouldn’t be the case if you were at 0.5 and then went up to 0.4 within a few days. Lol. Both of my events took place at much gradual intervals. Over the course of weeks. I’m currently sitting at 0.365 ppm and the tank looks pretty darn good. Obviously the color isn’t as vivid as .05, but it’s not too far off.



I know several of you stick heads here run higher nutrients and I’m just wondering if you’ve experienced the same at higher phosphate levels and at what levels did you see browning or did you see any at all, because every system is different. Corals will adapt if the target is achieved gradually!

I think Richard Ross is a prime example of that. If I recall correctly he’s been up to 1-2 ppm PO4. Not 0.1-0.2, but yes….1.0-2.0 ppm with Acro’s and the corals look decent. Also, Sanjay was keeping his tank at 0.4 ppm PO4 and 50 ppm NO3 for a long time. Not that he targeted those numbers, but I believe he said the tank just kinda settled there. We all know Sanjay grows corals pretty fast. Although, I do remember him saying he saw faster growth when he decided to take the levels down a bit.


With that said, where are you at currently and have you had better success at higher or lower levels of Nitrate and Phosphate? By success I mean survival, growth, and color. If your coals are vivid, but your loosing 25 Tenuis each year, I’d probably not define that as success. Which corals have you noticed having issues with higher or lower levels? Post a few pics and let’s
dialogue.

Remember, we can all learn from one another and everybody has their own opinions or preferences for their own tank. We can be civil and disagree and it’s OK! I can tell you, this dry rock system I have just doesn’t like low phosphate (currently), and I just don’t know why. That will likely change later, but the tank simply does better right now if the PO4 is 0.12 ppm or higher. 0.45ish seems to be the limit. After that it will start to grow some GHA. Every system is different and what may work in one system may be hard to achieve in another.

Cheers!


Here we have a Garf Bonsai loving life in 0.36 PO4.

I try to keep phosphate around 0.1. If my phosphate rises above 0.2, then the acropores darken, especially those that are yellow. Nitrate does not bother me at all, even if the test shows zero

 

[am3gross]

This is a very good read with lots of great info.

My levels are

Nitrate less then 5 ( trying to raise to 10-20)

Phosphate is around .05-.1--- Sometimes it does get a bit higher, which is when I will cut back on the Phyto or "extra" food I put in the tank.

I think all my colors look good currently and growth has been great.

 

[Reefahholic]

I typically ran phos really low, but I water changes with probiotic salt and don't have big dishes in my 32 gallon. I sat around .02-.04, with nitrates at 5-8.

However, I was trying to get rid of some bryopsis and doses Reef Flux. This jumped my phosphates (that and not dosing live phyto) to .36. I didn't have any losses, but it shocked me. I don't want to make fast changes, so it's been slowly dropping over the last two weeks about, at .19 as of yesterday's test. I was curious as to why .36 didn't kill off the acros, so interesting read on this thread. I had no idea others ran it so high.

A 0.32 jump is massive. Every tank is different, so I believe you go lucky. I’ve had a couple Acro’s die with a 0.15 swing.