Starting With 0 Nutrients then Dosing

[jda]

One of my theories about why some frags tend to drag in some tanks yet take right off in others is related to the ability to catch live tiny particles in the slime coats. Although I have had some frags just sit for a long time, I mostly have frags grow at the same rate as colonies from the jump. Although there is no way to really measure this, I do have a very diverse ecosystem that I refresh occasionally with ocean live rock and the whole tank is teeming with life. The ability for the frags to not spend any energy converting no3 to nitrogen, and also to assimilate the bacteria in the slime coat with nearly no energy loss for their building blocks is a big factor IMO. I do not have limiting levels of no3 or po4, but they are near ocean-level - this does make calcification faster in most cases.

I think that this is why every tank has different rates of growth and things.

 

[jda]

I also like to point out that while most people worry about N and P, they are not energy. More does not help you. They are not like sugars. Light still gives the coral most if it's energy through the zoox (not NPS) and they can also get carbon from things that they catch. Increasing light can/might/will make corals grow faster and be healthier, but once you have a surplus of N and P, more does not do anything.

I have always wondered how the oft-forgotten stepchild of the building blocks fits into reefing. Sulfur is required for life too. I have very little knowledge of how this works in a reef tank.

 

[Icryhard]

Hello, I was just reading through a thread about nutrients and read that someone uses a fuge and skimmer to almost constantly keep their nutrients at 0, then they dose what nutrients are needed with plus NP. Has anyone done this with any success? It seems like it would be nice to be able to control nutrient numbers pretty precisely so that they are always where we want them to be.

Your name looks a lot like mine.

 

[Pod_01]

There are articles that indicate that most true corals, and anenomes, prefer other forms of phosphorous than from orthophosphate. None of them have said that they cannot use orthophosphate. There is a three day windows in one accidental experiment where metaphosphate turns into orthophosphate - never seen any tests anywhere with any knowledge on this. Metaphosphate seems preferred since it is often bound to other things that the host can use to clean house (bind something else to and export), or in some other thing. There are not a lot of studies on this and a few of them needed to be translated, so who knows if any of it is true. I tend to believe it since while GFO seems to harm corals since it can bind many types of phosphates (meta and ortho), LC does not seem to harm corals by binding ortho - this is all anecdotal/observational, but it does line up.

Mature tanks with a wide variety of organisms do have bacteria and other microfauna that can be caught in the slime coats of true coral and assimilated without much energy. Larger colonies have the math advantage over frags. I am talking about tanks with ocean-like fauna and not things just from a bottle, most likely.

All evidence suggests that all corals can also get nitrogen from these organisms that they assimilate and also easily from ammonium. Not all seem to be able to use nitrate for nitrogen, but the ones that do have to use energy to convert it that nobody seems to know the exact amount - estimated in the 30-70% range. Because some things cannot use no3 at all, I would never dose no3 to help corals and only if you want to growth limit dinos or cyano or something like that. To each their own.

You have to kinda separate out the folks who tell you that their tanks and corals are awesome because they have no3 and po4 at pretty high levels. It was likely that the feedings that got the higher no3 and po4 levels is what did the work, not just having those levels.

Just from my observation GFO use for me was disaster while LC was not. Your explanation is lot better vs me scratching my head.
I also see your explanation working for NO3, my tank has none that I can measure. But I do feed the fish and do add Amino as well. I believe the fish and snails produce ammonium . Corals are doing well, not show case well but they are not dead. I am worried that since I don’t have any NO3:

that indicates deficiency.

Where I am there is no live rock unfortunately and I suspect that is my biggest issue. I don’t have sufficient diversity of life in the tank.

 

[jda]

If my theory is right, then the corals are getting P from other forms that we cannot measure (non ortho forms) and that those forms are effective. We have no idea what forms those could be, but we do know that they start with feeding fish. This is why I have no love for dosing po4 directly instead of feeding fish for coral benefit - again, if you are looking to growth limit dinos, cyano, etc. then dosing orthophosphate might be OK, but I don't do that.

My tanks have had .1 ish no3 for decades. There is no way to raise it. If I added sodium nitrate, the sandbed bacteria would multiple and use it all up again. No issues in all of this time. While sand beds are out of favor (kinda stupid why, to me), having undetectable nitrate was never an issue in all of these tanks.

 

[Pod_01]

I also like to point out that while most people worry about N and P, they are not energy. More does not help you. They are not like sugars. Light still gives the coral most if it's energy through the zoox (not NPS) and they can also get carbon from things that they catch. Increasing light can/might/will make corals grow faster and be healthier, but once you have a surplus of N and P, more does not do anything.

I have always wondered how the oft-forgotten stepchild of the building blocks fits into reefing. Sulfur is required for life too. I have very little knowledge of how this works in a reef tank.

I see light more like a gas pedal in the car. The more you press the faster you go but if there is no gas it will not go. For corals similar I can add more light but if the building blocks N P traces etc… are missing they will stagnate and perish. But if all buildings blocks are in proper supply more light will likely equal more growth.
The trick is to figure out what those buildings blocks are and the interactions . For example since I started adding plankton the corals look noticeably better, even GSP (I have to trim it lot more vs before ).

 

[jda]

In your scenario, nearly no established reef tanks are out of gas, yet hobbyists want to fill up the trunk, back seat, washer fluid reservoir and everything else up with gas. It is a good thing that cars have gas gauges.

I doubt that your coral are doing anything with the plankton. Would have to know the type of coral and type of plankton to know for sure. Plankton supplements have been around since the mid 1990s and the only difference in them has been if they are a punchline or are soon going to be a punchline. You can barely find anybody who quit using them that noticed a difference and it was like a maturity point in their system or in them as a hobbyist that coincided with any bump.