What does WWC know that you don't?

[andrewey]

Pardon the provocative title, but I wanted to introduce a discussion of nitrate levels in the reef aquarium. Most individuals aim to keep their nitrates below 5 ppm (1) , so I thought it would be noteworthy to discuss the reason for this and why this is sought after (calcification rates, coloration, health of the coral, etc.).

As a springboard for discussion, I thought it was interesting that WWC tries to maintain their nitrates at 10-20 ppm. (2) While I'm not trying to suggest they are the final authority for reef chemistry, it is interesting that generally speaking, it would seem that a majority of reefers would be pleased to own one of the WWC show tanks, yet most reefers that are purchasing corals from WWC seem to disregard their nitrate parameters.

Sources:

(1) http://www.reefcentral.com/forums/poll.php?do=showresults&pollid=7960

(2) http://ecotechmarine.com/wp-content/uploads/2016/11/World_Wide_Corals_Coral-lab_03.pdf

 

[blennyfromtheblock]

It's interesting that a few years ago, many reefers seemed to be chasing near-zero nitrate levels, and now the more fashionable range seems to be something like 0.25-3 ppm, yet many others (WWC being a great example) clearly have tremendously successfully tanks with much higher levels... curious how we appear to be much more concerned with number-chasing for this particular parameter, whereas most reefers will acknowledge the possibility of success within a wide range of values for other parameters.

 

[AllSignsPointToFish]

I think the acceptable range is quite wide. However, consistency is the key. Large, quick changes in nitrates can have significant impact. As long as phosphates are low, nitrates are consistent, and there is a plethora of herbivores in the tank, I can very easily see how 10-20 ppm nitrates would work just fine.

 

[fragit]

There are a few threads going on here about this very subject. There are many very successful reefers on here including myself who are keeping their nitrates at much higher levels 5ppm and up. Currently I am dosing spectraside stump remover (KNO3) to keep my nitrates between 10-20ppm. Last check was Monday and I'm at 16ppm, while I am striving to keep phosphates below 1ppm. Last check for phosphates was on sunday and they were at 0.04ppm. My sps seem to be doing well at these levels. I was running ULNS when my tank was first established and that killed my frags.

 

[Randy Holmes-Farley]

Pardon the provocative title, but I wanted to introduce a discussion of nitrate levels in the reef aquarium. Most individuals aim to keep their nitrates below 5 ppm (1) , so I thought it would be noteworthy to discuss the reason for this and why this is sought after (calcification rates, coloration, health of the coral, etc.).

As a springboard for discussion, I thought it was interesting that WWC tries to maintain their nitrates at 10-20 ppm. (2) While I'm not trying to suggest they are the final authority for reef chemistry, it is interesting that generally speaking, it would seem that a majority of reefers would be pleased to own one of the WWC show tanks, yet most reefers that are purchasing corals from WWC seem to disregard their nitrate parameters.

The two main issues with elevated nutrient levels are browning of corals due to elevated zoox, and excessive growth of algae.

Both of these can be prevented in other ways (although maybe not optimal for other reasons), and corals may grow faster in elevated nutrients even if they do not look their "best". Hence coral farmers may have different criteria than home hobbyists.

Also, how much inorganic N and P are needed for "optimal" aquaria will certainly depend on what is in the tank, and what other sources of N and P are provided to the aquarium (e.g., as foods corals can consume). .

 

[Randy Holmes-Farley]

For example, they control algae with fish. That's a great plan, if the home tank can accommodate and the hobbyist wants those sorts of fish.

But what if its too small for most algae eating fish?

What if you don't want them, or have organisms they may themselves eat?

 

[andrewey]

Out of curiosity, has anyone noted any effects of elevated nitrates beyond coloration and growth rate (increased/decreased resistance to pests, incidence of rtn or stn, etc). For the purposes of this question, I'm assuming all other parameters are within an "acceptable/ideal range".

 

[lennyd19]

Very interesting thread. My NO3 was over 50 and my corals have never looked better in growth and coloration. I am trying to get them in to more 10-20 range. I am curious as to what test kits you guys are using to get such accurate numbers?

 

[david.faik]

N to P to C ratios. Easier to keep P below N if 10-20ppm, thus avoiding cyano etc.

Lighting. WWC also (from memory) run their lights longer than 12 hours. I'd guess lighting factors into this. If your lighting is too low then the corals won't be able to use all the fuel, I think. Higher N (well than ultra low etc) means you can crank up the lights more, again I think. Put another way, high lighting low N will burn out your corals and higher N low lighting will brown out your corals

Comments?

 

[Daniel@R2R]

The two main issues with elevated nutrient levels are browning of corals due to elevated zoox, and excessive growth of algae.

Both of these can be prevented in other ways (although maybe not optimal for other reasons), and corals may grow faster in elevated nutrients even if they do not look their "best". Hence coral farmers may have different criteria than home hobbyists.

Also, how much inorganic N and P are needed for "optimal" aquaria will certainly depend on what is in the tank, and what other sources of N and P are provided to the aquarium (e.g., as foods corals can consume). .

I think the interesting thing about the OP's observation is that WWC doesn't have browned out corals. In fact, most hobbyists would strive to see their corals look like the ones at WWC.

 

[fragit]

Light intensity and flow are important factors in this equation. To answer the question about test kits... @andrewey I use red sea pro nitrate, and it is just a guesstimate because the user is trying to match colors. So my best guess at my nitrates is somewhere around 16ppm it could of course be higher and probably is.

 

[Randy Holmes-Farley]

I think the interesting thing about the OP's observation is that WWC doesn't have browned out corals. In fact, most hobbyists would strive to see their corals look like the ones at WWC.

Right. Zoox can presumably be limited in other ways. Folks have speculated that low availability of iron, for example, can limited algae and possibly zoox in high nutrient tanks. Whether that is desirable may depend on what else you keep in the tank.

 

[Preme]

I keep my levels around 5-10. My corals seem to have better polyp extension with this range, also better color And growth rates. I think as mentioned above being consistent is a big factor to success, for example someone who for 3 days has levels of 10-15 then 2 days later has 20-25 then back down and then back up, may not have as good looking corals compared to someone who has a steady level of 15-20. I also don't think people should really pay as much attention and go chasing levels, just because 5 or below works for some people dosent mean it will fit you.
I like to check my water weekly if my corals are open,and have good color I keep my levels near to what they're at.

Also as mentioned above lighting and flow are in my opinion the 2 biggest keys 2 success with SPS particularly. You basically just have to find what works best overall for you!

 

[andrewey]

To throw my own experiences into the mix, I used to run all my systems as ULNS (0-1 ppm nitrate, phosphate 0.01-0.04). As of late, I've noticed my sps have their best coloration somewhere between 10-15 ppm (with the added benefit of increased growth). My personal belief (non-scientific) is that there isn't a one size fits all approach to nitrate- rather it's a parameter with an acceptable range similar to alkalinity where different levels produce the "best" results for different systems, likely due to each tanks individual parameters and other variables.

 

[AllSignsPointToFish]

Very interesting thread. My NO3 was over 50 and my corals have never looked better in growth and coloration. I am trying to get them in to more 10-20 range. I am curious as to what test kits you guys are using to get such accurate numbers?

I've used both Red Sea and Salifert nitrate test kits. While not exactly identical, they have very similar resolution and accuracy limits.

 

[beaslbob]

looks to me like that are maintaining a redfield ratio

 

[andrewey]

I'm not sure how those running higher levels of nitrate even come close to the redfield ratio. If we take the example of WWC, they aim for 10-20 nitrate and .03-.08 phosphate, which at the lowest permutation is almost 10x the redfield ratio of N to P

 

[Jizu Puentes]

What are ypu guys running your Alk at with these higher levels of N? Last I check my N and P were barely readable on a Salifert kit but I have cyano in my macroalgae tank as well as a little in my main display with all corals still looking great. My Alk is at 7.8.

 

[andrewey]

I've run my alk anywhere from 7-11 when my nitrate was above 10 and never really noticed a difference beyond coral growth.

 

[Reefltx]

Very interesting thread. My NO3 was over 50 and my corals have never looked better in growth and coloration. I am trying to get them in to more 10-20 range. I am curious as to what test kits you guys are using to get such accurate numbers?

Ikr, I use salifert and all I can tell is my no3 is somewhere between 10 & 20ppm. I don't see how many can get so accurate numbers with these color charts to go by. Hanna needs to come out with a nitrate checker.