Red Sea DKH vs an Ultra Low Nutrient system

[Bearjohnson]

Perhaps someone can shed a little light on this subject.

I've been doing a little reading on Ultra Low Nutrient Systems (ULNS) and I also have looked into the Red Sea program.

All of the information I have read states that when running an ULNS with bio-pellets or any other introduced carbon source in an effort to feed bacteria to combat excessive nutrients the DKH should be between 7-8.5.

When I read information regarding the Red Sea Coral Program, they say that the DKH for accelerated growth should be around 12.1.

So, what's the deal with such a swing in recommended programs?

Why does the write-ups on ULNS differ so greatly from a program such as Red Sea?

 

[reefer gladness]

Not familiar with the Red Sea program but I've heard from multiple sources including my trusted LFS that specializes in SPS that dKH should be kept between 7-8 dkH when running activated carbon. I'm guessing the Red Sea program doesn't include activated carbon.

 

[Bearjohnson]

Do we have any idea why when running carbon the dkH should be ran between 7-8 and what are the consequences of running it higher?

 

[reefer gladness]

Most of what I find is what I consider anecdotal evidence but that's a large part of our hobby. When researching this on other fishy forums it seems the general agreement is that running alk at levels higher than NSW are resulting in tissue necrosis and burnt tips, these were mostly SPS coral tanks.

Wish I could find a scholarly article from Rand Holms-Farley to explain it simply but what I have found was pretty hard for me to follow. My LFS is VividAquariums.com and they also mention "alkalinity (8-9.5 dkh - run it 7-8 if you are carbon dosing)", under the water chemistry requirements for the corals they sell. Might try dropping the question on the owner Dave. I remember asking him about it last year and he just said they had problems with burnt tip on their acros with high alk - sometimes, but I didn't ask him for a further explanation.

 

[Bearjohnson]

For some strange reason I've always believed that keeping alk at the higher end of the spectrum (9-10) would be more beneficial than maintaining in the lower end.

 

[saltfan]

I run mine at 9 ( all corals good ) just to give me some cushion either way. I would hate to be running at 7-8 and have it drop for some reason.

 

[Mike Johnson]

I did the Red Sea Program a couple years ago. Actually they suggest 12.6 dKH for accelerated growth. I've come to the conclusion that is ridiculous. I did that - my corals all turned brown. Red Sea recommends 8.2 dKH on mature/low nutrient systems. My corals are much happier, more color, around 8.4. I don't want to go any lower because around 7 you're risking RTN. I've found anything above 10 and the corals turn brown. Maybe they grow, but they're brown. I try to keep my levels at = Alk 8.4 dKH, Cal 430, and Mag 1350.

 

[PSU4ME]

Nice having vivid as you LFS! To the dkh, I believe 12 is ridiculous as Mike said. These corals come from the ocean and we strive so hard to recreate their natural environment so pushing anything other than natural params doesn't make sense to my...... And I'm talking sps. It seems that making more available speeds up growth but at the expense of color IMO. My stuff grows too fast anyway . I keep my tank in the low 7's