BB vs. SB

[Deanos]

Another part of being BB is having that huge skimmer to keep your nitrates down .

Aaahh!! I see you have it backwards The fact that you don't have a DSB to break down nitrates, is why you must have a big skimmer. The requirement of having a big skimmer to maintain a BB tank can considered a negative by people not willing to spend extra money. For them, a few extra bags of southdown in a remote location will do the same job as a huge skimmer, more flow pumps and a filter sock.

 

[jackson6745]

Dean I sort of disagree. In a DSB I think a big skimmer is just as important to prolong the life of your sandbed and to keep PO4 down. IME a DSB does help to keep nitrates down but phosphates can become problematic unless the tank is skimmed properly. A remote SB will not do the same job as a quality skimmer.
It basically boils down to how much $$ you have spent on your setup and what type of corals you keep to determine if a large skimmer is cost effective.

 

[Deanos]

Dean I sort of disagree. In a DSB I think a big skimmer is just as important to prolong the life of your sandbed and to keep PO4 down. IME a DSB does help to keep nitrates down but phosphates can become problematic unless the tank is skimmed properly. A remote SB will not do the same job as a quality skimmer.

No need to disagree. I'm not undermining the importance of a big skimmer on any tank. I was simply telling Kris, that a bigger skimmer is not an advantage on a BB tank, it's a requirement. Whereas, on a tank with a sandbed that's addressing nitrates, you can get away with a lesser skimmer and still have pristine water.

 

[nanoreefer22]

No need to disagree. I'm not undermining the importance of a big skimmer on any tank. I was simply telling Kris, that a bigger skimmer is not an advantage on a BB tank, it's a requirement. Whereas, on a tank with a sandbed that's addressing nitrates, you can get away with a lesser skimmer and still have pristine water.

I know it's not an advantage . You could throw a huge skimmer on a huge tank, I realize that without a big skimmer on a BB tank nitrates would get out of control because theres no means of cleaning the water. Nothing was backwards, just a little misphrased.

 

[jackson6745]

No need to disagree. I'm not undermining the importance of a big skimmer on any tank. I was simply telling Kris, that a bigger skimmer is not an advantage on a BB tank, it's a requirement. Whereas, on a tank with a sandbed that's addressing nitrates, you can get away with a lesser skimmer and still have pristine water.

I totally agree I misunderstood

 

[kimoyo]

Aaahh!! I see you have it backwards The fact that you don't have a DSB to break down nitrates, is why you must have a big skimmer. The requirement of having a big skimmer to maintain a BB tank can considered a negative by people not willing to spend extra money. For them, a few extra bags of southdown in a remote location will do the same job as a huge skimmer, more flow pumps and a filter sock.

I don't know about this. Speaking about SPS because thats all I've read about so far :lol:.

There are two issues.

Nusiance algae growth, which is limited by phosphates.

Zooxanthellae growth, which is limited by nitrates (and phosphates possibly).

I haven't seen a model yet for nitrate uptake in corals but I believe you can have good color and growth with high nitrates under certain conditions. This is further support by certain member tank with high nitrates but great coral color and growth. So I'm not sure how important a big skimmer is anymore (although I want one).

 

[Tonyscoots84]

Its always a good thing to have a BIG SKIMMER....

 

[kimoyo]

Its always a good thing to have a BIG SKIMMER....

If your talking about limiting algae growth in the tank (which I want), I agree.

But if your talking about coral health and color I'm not so sure yet. I can think of two tanks from this site that would seem to go against this.

 

[ShaunW]

I think alot has to do with what species of macroalgae has been introduced to ones tank. Limiting algae growth through nitrate and phosphate control works (bigger skimmer, DSB), but preventative medicine always works better. Therefore, never introducing species of algae that thrive in oligotrophic waters and are able to derive all their energy requirements through photosynthesis is another piece to the puzzle.

Additionally, algae growth is always going to be depending on the most limiting molecule. If nitrate is in excess, but some other nessesary requirement for growth is absent, then regardless of the nitrate levels, algae will not grow.

 

[jackson6745]

If your talking about limiting algae growth in the tank (which I want), I agree.

But if your talking about coral health and color I'm not so sure yet. I can think of two tanks from this site that would seem to go against this.

When you come up with a theory LMK please. Seeing Pierces tank confuses the $hit out of me compared to other SPS reef I have seen.

 

[griMReefer]

aesthetically, i like BareBottom better because once your reef is mature you get all that nice thick coralline encrusting over itself all over the bottom of the tank, and it gives that DEEP water slice-of-the-ocean "abyss" look while sand gives more of a shallow "mini-reef" or "portrait" look.

 

[kimoyo]

When you come up with a theory LMK please. Seeing Pierces tank confuses the $hit out of me compared to other SPS reef I have seen.

You sould see Adrian's (ricordiaking) frag tank :lol:.


I've been asking around to see if there are any models for nitrate uptake and if I find them I will post here. I included the accepted model for ammonium uptake by corals at the bottom of this post.

Pierces system has 40ppm nitrates but still has great color and growth in his display. But his frag tank, which he is using old bulbs in, has great growth but not color.

What people believe now is that the coral and zooxanthellae draw from the same pool for carbon. So that when the zoox increase in population they are then outcompeting the coral for C thus preventing the coral from performing calcification. But it has been shown that high levels of ammonium or alkalinity or CO2 can negate the effects of high nitrate on coral growth.

It has also been shown that chlorophyll pigments darken in low light levels (remember they are most effective at specific wavelengths).

Some corals have not been shown to expel zoox. Its assumed that the coral controls zoox growth by limiting transport of nutrients to zoox. But I haven't seen a model that explains what happens to this transport mechanism in high nitrate levels.

Here's what I think and it could be wrong. Peirce might have high levels of zoox in his corals. But something (high levels of ammonium, CO2, alkalinity, or combination) is still allowing him to get good growth. And his lights are providing good enough light (remember he runs a longer MH photoperiod) that his colors are still coming thru; evidenced by the fact that his corals brown in his frag tank.

BTW, I know you told me when we were talking about your fishload coloring up your corals that you thought it was the amino acids from the fish poop. But that is a very small percentage of what the corals actually use. Most of there requirements are met thru ammonium assimilation (the model below) which leads to AA's but this might still fit in well with the large fish population thing.

Click to enlarge.

 

[cali_reef]

Seeing Pierces tank confuses the $hit out of me compared to other SPS reef I have seen.

You guys are confusing the $h!t out of me.. I have tried both DSB and some what a BB(because my fish only tank have a SSB and is connected to my reef tank), both have their advantage and disadvantages. Here are my experiance with them:

My old 150 gallon tank did very well with a 6-8" sand bed, some of the sand in there were over 5 years old when the tank was broken down. I did minimum water changes (less than 10% and not more than once every 2-3 months), No3 and Po4 was undetectable using a ETS 800 as the only skimmer. You guys know how I like to stock my fish so the bio load is not lacking in anyway. I think the sand bed was doing the things it needs to do in that tank.
Here is a full tank shot for reference:

For Rich:

On my new 150 reef, I decided to go BB because everyone was doing it and I wanted more flow. The fine grain sand always caused my pump seals to leak over time and I am tired of replacing seals on my close loop pump, so no sand at all in this tank now. I also have a 180 gallon with a 1-2" sand bed full of fish connected to this system, along with few other tanks making the total water volume about 600 gallons. I had a 40 gallon refugium with a 6" sand bed but I decided to pull the sand out two weeks ago to see if that had any effect on the system, so far the perimeters are the same.
Well, my No3 is 50ppm and Po4 is anywhere from .3 to 1 at times for the last 12-18 months, I do 5-10% water changes a week and the levels are not going down even with two large skimmers skimming wet. With that I believe a DSB does help keep the levels down if you want to keep lots of fish in a reef\fish tank, go BB if you want to have flow but you will need other means to control the excess No3 and Po4.

 

[ShaunW]

Based on your description of your system your nitrate levels make sense. You lack the biological means to remove it naturally.

Cali, can you post the above post on the new nitrate thread, I am going over there to discuss this cool issue. It no longer belongs in a newbie forum, .

 

[jackson6745]

ETS skimmers are the best...LOL

I laugh everytime someone tells me that

 

[jiggy]

sand is not needed as a buffer, and it is not needed for filtration.. liverock does it all.. u just need a good amount of liverock.. at least 1.5lbs per gallon.. i have 180lbs of liverock in my 120 and i bet it works just as good as any dsb.. it has enough beneficial bacteria on it to break down unwanted impurities in the water, and also works as a buffer.. alot of flow works well so the water can be moved through the liverock, just like how water is moved through biofiltration on a powerfilter or canister..

i prefer CB.. coralline bed.. =)