Help me understand something about nitrates and phosphates

[reef_ninja]

As some of you know, I have a 40 breeder mixed reef. Getting mixed results with my corals: birdsnest, poci, duncans are doing great. Acros, acans, zoas, and a small button scoly.....not so much. Acans are always about halfway shrunk, zoas are sometimes open, sometimes not, never look 100% happy. Im pretty sure my problems are two part: the lighting was pretty intense (I addressed this, corals have responded well so far) and my nutrients. My NO3 and PO4 are a solid zero, and have always been so.

Now I trust Randy's articles and advice, not questioning it at all, but there's a huge gap Im seeing with advice on here and what's in the article (http://reefkeeping.com/issues/2006-09/rhf/index.php), which makes me think I'm missing something. For example, based on the article, sources of phosphate include sources such as fish poo and dried and frozen food. It also states that skimmers are responsible for removing the inorganic wastes that will raise phosphates.....

So....why is it that there are so many comments on here about how increasing your feedings and shortening skimmer times wont increase phosphates? At the same time, why is it that I can feed 3 times as much as before, and have zero testable difference in nitrates and phosphates?

I resorted to dosing nitrates and phosphates in the last week, and TBH, Im bothered by it. It just seems that there should be a better way as opposed to dosing something so specific. In my profession, I tend to look "up the river", and dosing nitrates and phosphates seems to be a bandaid that doesn't really get to the root?

I am dealing with a little bit of algae (I was using Vibrant for a short time, and stopped this), but my only exports are WCs every two weeks, live rock from KPAquatics, and a Curve 5 skimmer. Imports include feeding heavy frozen food 1-2 times a day, and pellets about once a day as well. Stocked with 4 fish (maroon clown, clown goby, dottyback, lawnmower).

What am I missing?

 

[HomebroodExotics]

Either feed more or reduce nutrient export methods. But honestly I’m seeing some great tank running almost zero nutrients. Would love to know the difference. I suspect it has something to do with what the corals are eating.

 

[Cory]

If you look at old tank of the months (2000) they all mostly had metal halides/t5s and 0/0 for no3 and po4. They also mostly used powerful protein skimmers. Also had deep sand beds. Id suspect as long as there are a slow increase in nutrients but its consumed fast enough, im there shouldn't be an increase.

 

[T-J]

If you have algae, then you aren't a solid 0 on your nutrients. So here's what MIGHT be happening:

You algae is consuming nutrients at the rate they are being produced, which will give you a 0 test reading.
Another possibility is that your rocks are absorbing phosphate. At some point they will become saturated and start to release it back into the water. I know this happens with dry rock, not sure if it can happen with live rock.

One of the things I've learned in my 20+ years of reefing is to use a lot of the advice I find as great guidelines or starting points. Every system is different, and I've seen tanks flourish under conditions many reefers would consider a death sentence! Use what works for your tank.

 

[reef_ninja]

Good point, Ill have to look at old TOTMs. I think for me, I just dont want to get caught up with chasing numbers and missing the big picture. Forgot to mention Im also using reef roids 2-3 times a week as well. Im thinking about adding another fish or two as well......

 

[reef_ninja]

If you have algae, then you aren't a solid 0 on your nutrients. So here's what MIGHT be happening:

You algae is consuming nutrients at the rate they are being produced, which will give you a 0 test reading.
Another possibility is that your rocks are absorbing phosphate. At some point they will become saturated and start to release it back into the water. I know this happens with dry rock, not sure if it can happen with live rock.

One of the things I've learned in my 20+ years of reefing is to use a lot of the advice I find as great guidelines or starting points. Every system is different, and I've seen tanks flourish under conditions many reefers would consider a death sentence! Use what works for your tank.

I like this, but this tank I have now is something else. What worked for me before just doesnt seem to cutting it. Its been about 9 months now, figured I would have hit a stride with the LR maturity by now.

 

[b.clark]

If your NO3 and PO4 are a solid zero I have heard you need to run a low alk. Level of around 7.5 dkh anything over 8 and certain corals will struggle

 

[HomebroodExotics]

If your NO3 and PO4 are a solid zero I have heard you need to run a low alk. Level of around 7.5 dkh anything over 8 and certain corals will struggle

Interesting theory. Thanks for that. Would anyone know more about this?

 

[b.clark]

I am looking into this more now for myself. I’ve read a couple of arrivals on low nutrient tanks by Randy and lower alk helps

 

[Randy Holmes-Farley Verified Community Expert]

As some of you know, I have a 40 breeder mixed reef. Getting mixed results with my corals: birdsnest, poci, duncans are doing great. Acros, acans, zoas, and a small button scoly.....not so much. Acans are always about halfway shrunk, zoas are sometimes open, sometimes not, never look 100% happy. Im pretty sure my problems are two part: the lighting was pretty intense (I addressed this, corals have responded well so far) and my nutrients. My NO3 and PO4 are a solid zero, and have always been so.

Now I trust Randy's articles and advice, not questioning it at all, but there's a huge gap Im seeing with advice on here and what's in the article (http://reefkeeping.com/issues/2006-09/rhf/index.php), which makes me think I'm missing something. For example, based on the article, sources of phosphate include sources such as fish poo and dried and frozen food. It also states that skimmers are responsible for removing the inorganic wastes that will raise phosphates.....

So....why is it that there are so many comments on here about how increasing your feedings and shortening skimmer times wont increase phosphates? At the same time, why is it that I can feed 3 times as much as before, and have zero testable difference in nitrates and phosphates?

I resorted to dosing nitrates and phosphates in the last week, and TBH, Im bothered by it. It just seems that there should be a better way as opposed to dosing something so specific. In my profession, I tend to look "up the river", and dosing nitrates and phosphates seems to be a bandaid that doesn't really get to the root?

I am dealing with a little bit of algae (I was using Vibrant for a short time, and stopped this), but my only exports are WCs every two weeks, live rock from KPAquatics, and a Curve 5 skimmer. Imports include feeding heavy frozen food 1-2 times a day, and pellets about once a day as well. Stocked with 4 fish (maroon clown, clown goby, dottyback, lawnmower).

What am I missing?

That article of mine, and the advice in it, was written 15 years ago. Since then, folks have become more successful in driving nitrate and phosphate "too low" than they were previously, and that has led to problems such a dinos and "starving:" corals.

The real problem seems to be the lack of particulate foods in our tanks, and the excessive reliance of aquarium corals on inorganic nitrate and phosphate to get enough N and P, making matching the ocean a very poor plan with respect to nitrate and phosphate.

 

[HomebroodExotics]

That article of mine, and the advice in it, was written 15 years ago. Since then, folks have become more successful in driving nitrate and phosphate "too low" than they were previously, and that has led to problems such a dinos and "starving:" corals.

The real problem seems to be the lack of particulate foods in our tanks, and the excessive reliance of aquarium corals on inorganic nitrate and phosphate to get enough N and P, making matching the ocean a very poor plan with respect to nitrate and phosphate.

If I am understanding what you are saying correctly. Would increasing particulate foods in the tank and decreasing N and P should balance things out? Simply put of course.

 

[Randy Holmes-Farley Verified Community Expert]

Interesting theory. Thanks for that. Would anyone know more about this?

it is well known that burnt tips on some SPS corals is caused by higher alk and low nutrients. One likely theory to explain it is that the skeletons (using alkalinity) grows faster than the tissue (using nitrate and phosphate) can keep up.

 

[Randy Holmes-Farley Verified Community Expert]

If I am understanding what you are saying correctly. Would increasing particulate foods in the tank and decreasing N and P should balance things out? Simply put of course.

Yes, but it presumes that you can provide what they need. The Zeovit approach to ULNS tanks takes this sort of approach.

 

[HomebroodExotics]

Yes, but it presumes that you can provide what they need. The Zeovit approach to ULNS tanks takes this sort of approach.

Awesome. Thanks for the info, this has connected a lot of dots for me.

Oh wait one more thing. What would be the zeovit product that handles this food particle if you would happen to know right off hand? Thanks, they have so many.

 

[WirelessMike]

Watching along as this is great info!

 

[Randy Holmes-Farley Verified Community Expert]

Awesome. Thanks for the info, this has connected a lot of dots for me.

Oh wait one more thing. What would be the zeovit product that handles this food particle if you would happen to know right off hand? Thanks, they have so many.

Zeovit does not explain what is in every product, but the link below shows many zeo products claimed to be coral foods:

https://s3.amazonaws.com/brsinstructions/Korallen+Zucht/korallenzucht_katalog_2014_englisch.pdf

Amino acids are widely used (including in Pohls extra special ) to provide N in a low nitrate system. Not particulates, necessarily, but an organic compound source of N.

 

[reef_ninja]

That article of mine, and the advice in it, was written 15 years ago. Since then, folks have become more successful in driving nitrate and phosphate "too low" than they were previously, and that has led to problems such a dinos and "starving:" corals.

The real problem seems to be the lack of particulate foods in our tanks, and the excessive reliance of aquarium corals on inorganic nitrate and phosphate to get enough N and P, making matching the ocean a very poor plan with respect to nitrate and phosphate.

*Edit: Whoops, missed the above posts, let me go through those first.

 

[Dkmoo]

here's a chart i did a while a go that help highlight how nutrients go thru a reef tank - it doesn't have everything, but does highlight most of the important relationships and how various export methods impact it. As you can see - "no3/po4" for the most part is a waste product that primarily drives algae growth. While corals does uptake a portion of it to get to its N and P sources (mostly via the zoox absorption), corals much more prefer other forms of N and P sources in the form of dissolved organics, target fed coral foods, or dosed protein/amino acids. I think thats probably the gap you were looking for: No3/Po4 != coral nutrition.

 

[reef_ninja]

That article of mine, and the advice in it, was written 15 years ago. Since then, folks have become more successful in driving nitrate and phosphate "too low" than they were previously, and that has led to problems such a dinos and "starving:" corals.

The real problem seems to be the lack of particulate foods in our tanks, and the excessive reliance of aquarium corals on inorganic nitrate and phosphate to get enough N and P, making matching the ocean a very poor plan with respect to nitrate and phosphate.

Alright, lets try this again. What would you recommend for increasing particulates? Seems the reef roids should be covering this shouldnt it?

 

[blasterman]

The reason foods don't consistently drive up nitrates and phosphates is marine foods are inconsistent in terms of their composition. Mysis shrimp for example are mostly water. You can dump mysis all day in a tank and not see a nutrient spike. Also, if fish and corals are consuming food they will convert a large part of those proteins to their own needs and only the waste produced will result in nitrate and phosphate.

One way I've found to raise nitrates reliably with food is grind up some beef heart in a blender until its a puree (or any meaty fish food) and dump it in the tank. You *will* see a nitrate spike because the smaller particles will degrade to nitrate because they can't be consumed by fish and just slopping around in the water column where the protein is broken down in into ammonia. Also, zoas and palys love this. Not so much SPS.

Reef Roids drive up phosphate. Again, because they are small particles that aren't entirely consumed and as they decompose freely in the water column they increase nutrient levels.

My own opinion, but I've never been convinced SPS eat anything or need anything bigger than a molecule. The fastest SPS growth I've seen in high end SPS tanks and my own have been when nitrate and phosphate are at consistent levels and not bouncing around. On small tanks with high SPS consumption I can run calcium at 375 or 475. It barely affects growth. Phosphate or nitrate though bottoming though every couple of days can be visually seen in the tips of fast growing SPS as they slow and become more rounded. The amount of feeding these tanks get is highly variable......as long as those nutrient variables are consistent it's the most important factor....IMO. Dump expensive amino acids in a tank or phyto and I need to be convinced they just don't break down into ammonia and then nitrate.