So my water DOES need nitrates now??

[Rick.45cal]

IME, well fed sps are much hardier than starved ones. I've been experimenting with dosing NO3 and PO4 in a 38g skimmerless sps dominant tank. IMO, PO4 seems to be the (growth) limiting nutrient. My goal is the Redfield Ratio or thereabouts, so I try to keep NO3 between 2 to 5 ppm (dosing NaNO3) and PO4 between .1 to .2 ppm (dosing Seachem's KPO4 or feeding reef roids, roe, etc.). I've noticed that the corals seem to prefer the liquid PO4, and that if I add a few drops at night I also need to increase the amount of Alk supplement (i.e. carbonate, bicarbonate, etc.) that I dose. Of course, too much PO4 inhibits growth, although how much is too much appears to be species specific...at .5 PO4 purple stylo grew like crazy, as did a red planet colony, but other acros didn't seem to be growing much. And yes, the tank struggles with algae but not as much as you'd think. I recently added two tuxedo urchins, which is helping a lot (when they get through with a patch, the rock looks like dry rock from the box, lol). Still, would love to have a tank big enough for a foxface.

I dose NeoPhos from Brightwell aquatics when phosphate drops to near undetectable levels. I'll dose enough to bring the PO4 to .02-.04 ppm. Twenty years ago if you asked me if I ever thought I would be dosing PO4 I'd of said you were crazy.

 

[Randy Holmes-Farley Verified Community Expert]

Actually that's is exactly what it is about. NSW still has much much more available nitrate even thought the concentration is low.

I disagree. If the level is not dropping below the NSW levels, it doesn't matter if there is a trillion gallons nearby with additional nitrate. Organisms can only respond to, and take up nutrients from, the water in contact with them. That would be like saying you could suffocate in a small room with 20% O2 because there just isn't much around, while in the open air at 20% O2 you are fine because there is so much.

The difference is available organics (dissolved and particulate, including whole organisms) which contains lots of N and P.

 

[Fourstars]

So do the corals uptake NO3 and PO4 directly, or from plankton and zooplankton? I know my macro algae sure does better if I dose it. but don't see much difference in the corals.

 

[mcarroll]

So do the corals uptake NO3 and PO4 directly, or from plankton and zooplankton? I know my macro algae sure does better if I dose it. but don't see much difference in the corals.

Yes, and yes. Carbon too. Yes and yes.

Probably not at the same time, however.

If corals are able to feed heterotrophically, then they generally curtail or cease absorbing dissolved nutrients or translocating with their symbionts. If they haven't fed again within a few days, they will start translocating, etc. In general.

Many good papers circulating on this recently.

 

[Rick.45cal]

Yes, and yes. Carbon too. Yes and yes.

Probably not at the same time, however.

If corals are able to feed heterotrophically, then they generally curtail or cease absorbing dissolved nutrients or translocating with their symbionts. If they haven't fed again within a few days, they will start translocating, etc. In general.

Many good papers circulating on this recently.

You also can't forget that predation benefits the animal first and foremost, and dissolved nutrients benefit the symbiotic algae first and foremost. The excess is then passed on to the other. Neither can grow actively without both parts of the equation being fed. If we nourish the animal and the algae simultaneouly then the total organism is benefiting. If one or the other isn't nourished then the whole organism will suffer or growth will stall or halt.

Edited to add: Pretty sure that's what you already said upon rereading lol. Sorry

 

[Griff]

Great discussion! Following along!

 

[mcarroll]

You also can't forget that predation benefits the animal first and foremost, and dissolved nutrients benefit the symbiotic algae first and foremost. The excess is then passed on to the other. Neither can grow actively without both parts of the equation being fed. If we nourish the animal and the algae simultaneouly then the total organism is benefiting. If one or the other isn't nourished then the whole organism will suffer or growth will stall or halt.

Edited to add: Pretty sure that's what you already said upon rereading lol. Sorry

I don't think it can be said enough and I might've got it wrong or not said it clearly, so kudos!

As an aside...

How corals dispose of excess carbon is interesting to me. Algae (for comparison) can apparently decouple growth from their carbon-production processes and just release carbon byproducts into the water. Corals naturally can deal with excess carbon too, but with such a potentially unlimited/exasperating source of carbon as their algal symbionts, they are literally at risk from it them.....oxygen toxicity. I think when we boost the carbon content of the system it messes with this process of carbon elimination somehow.

 

[bif24701]

I disagree. If the level is not dropping below the NSW levels, it doesn't matter if there is a trillion gallons nearby with additional nitrate. Organisms can only respond to, and take up nutrients from, the water in contact with them. That would be like saying you could suffocate in a small room with 20% O2 because there just isn't much around, while in the open air at 20% O2 you are fine because there is so much.

The difference is available organics (dissolved and particulate, including whole organisms) which contains lots of N and P.

Agreed, however we all know that there is a lot of flow in natural reefs. The supply will constantly be replenished.

 

[willthethrill]

So I got 4 new small fish in QT. Im starting to feed a little heavier in the display, and I'm dosing Reef Energy A&B. And I'm on the fence about taking the dual gfo/carbon reactor offline temporarily. I'm still going to leave all the chaeto in the big refugium just as a cushion so there's not a big nitrate spike or anything. I'm also still continuing with the 20% bi-weekly water changes.

 

[Randy Holmes-Farley Verified Community Expert]

Agreed, however we all know that there is a lot of flow in natural reefs. The supply will constantly be replenished.

Yes, but that does not justify the conclusion.

 

[revhtree Verified Admin]

Great discussion!

 

[Vaughn17]

Tides and currents are essential for ocean ecosystems to function, i.e. no water movement, no life. That's my two cents worth.

 

[Newb73]

So I got 4 new small fish in QT. Im starting to feed a little heavier in the display, and I'm dosing Reef Energy A&B. And I'm on the fence about taking the dual gfo/carbon reactor offline temporarily. I'm still going to leave all the chaeto in the big refugium just as a cushion so there's not a big nitrate spike or anything. I'm also still continuing with the 20% bi-weekly water changes.

Just turn reactors and skimmer off for a few hours.

I trurn off my main pump and circ the treatment in the display only for an hour, then turn on the main. After a few more hours i turn the ozone and gac back on but ill usually leave the skimmer off over night

 

[willthethrill]

Just turn reactors and skimmer off for a few hours.

I trurn off my main pump and circ the treatment in the display only for an hour, then turn on the main. After a few more hours i turn the ozone and gac back on but ill usually leave the skimmer off over night

What treatment? Take a look at the beginning of the discussion

 

[Newb73]

What treatment? Take a look at the beginning of the discussion

........ I'm dosing Reef Energy A&B. .

^^^^^^^^^^^^This treatment ^^^^^^^

 

[Newb73]

And I'm on the fence about taking the dual gfo/carbon reactor offline temporarily. .

...and the response was...

Just turn reactors and skimmer off for a few hours.

I trurn off my main pump and circ the treatment in the display only for an hour, then turn on the main. After a few more hours i turn the ozone and gac back on but ill usually leave the skimmer off over night

 

[Scott.h]

I was at the point you were at when I came to the same conclusion. I went from 40 or 50 to zero over the course of a few months by doing a variety of different things. When I finally got down to undetectable or near undetectable for a period of time my softies especially started to look worse. As I backed off it was interesting to notice how some corals looked better with lower nutrients and some looked worse. I found a balance around 5. I don't feed much and only use coral food once a week. Seems to be working well.

 

[Nick James]

So I got 4 new small fish in QT. Im starting to feed a little heavier in the display, and I'm dosing Reef Energy A&B. And I'm on the fence about taking the dual gfo/carbon reactor offline temporarily. I'm still going to leave all the chaeto in the big refugium just as a cushion so there's not a big nitrate spike or anything. I'm also still continuing with the 20% bi-weekly water changes.

I'd leave your reactors online if you are increasing food input. One change at a time so you don't swing to fast the other way. Just my thoughts.

 

[Newb73]

I'd leave your reactors online if you are increasing food input. One change at a time so you don't swing to fast the other way. Just my thoughts.

The carbon and skimmer will immediately start removing the addidives which defeats the purpose of running them. In my case i run ozone and you REALLY are defeating the purpose by adding reef energy then cycling it through ozone This is also the reason you cant run uv on a zeovit tank.

Agree with what you said...thats why i recommended TURNING THEM OFF A FEW HOURS.....and NOT taking them OFFLINE.

 

[willthethrill]

^^^^^^^^^^^^This treatment ^^^^^^^

This was taken out of context. My original post was about having zero nitrates (nutrients) in the water and having slow coral growth. My next course of action was to add nutrients to the system via extra feeding, * turning off my reactors temporarily to let levels rise just a small amount, and also dosing reef energy. I wasn't turning anything off because of the reef energy (except skimmer). Id rather keep my main pump on so that my entire water volume is dosed accordingly, not just my display. which only has a fraction of my entire water volume. Again the purpose of all this is to bring nutrients up slightly in my entire system. However, you bring up a point as far as the carbon in the second reactor, but I don't think that's gona remove any of the beneficial stuff dosed in from the reef energy.