No3 & Po4 uptake questions

[vaughan5]

I have been doing a lot of reading lately. Specifically Eric B's atricles " Feeding the Reef". I came to the conclusion that I am underfeeding my system. My sand looked bleached white and my live rock was "sterile" looking. About two weeks ago I started to really up the amount of food at feeding time. I have been adding so much food that it clouds the entire tank. I also doubled the amount of DT's Phyto that I was dosing. In addition to the new feeding amounts I started turning the skimmer off before feeding, and leaving it off all night.

Let me describe my system before I get to the point of this thread.
100 Gal. AGA w/ 4"-6" DSB. & approx 100 lbs live rock.
Life Reef Vs-24 skimmer & Phosban reactor.
I have a very healthy 30 gal refugium with a 4" DSB consisting of mostly Walt Smith Mud. Its crawling with Mini brittle stars, Pods and Mysis shrimp. Also 4 sp. of Macro. Halmedia, Chaeto., and two sp. of Calerpa. The fuge is lit by a 65 watt coralife 50/50 PC bulb. Macro health and growth is great.
I have a very large bio load in the main tank but no matter how much I feed my tank, No3 & Po4 is always undetectable. I know this is what a lot of people strive to achieve, but I want my tank teaming with life.
It has been two weeks since starting the new feeding regimen and things are starting to look a little more alive. The population of Mini brittle stars and spirulonid (spelling) worms is through the roof. The only negative affect is a Cyano outbreak on some parts of my sand. This leads me to believe that Po4 & No3 still may be limited in my system. Am I over doing it with all the Macro in my fuge plus the Skimming and Phosban reactor ? My ultimate goal is to be able to go skimmerless and replace the Phos ban with Carbon. Any thoughts on why the Cyano outbreak ? Can I expect the system to adjust and the Cyano disappear ? I am really happy with my system and have no complaints. Only trying to do better.

 

[graveyardworm]

I have a similar setup which I've been feeding a bit heavily, and dosing KNO3 plus I was dosing iron and iodine, and feeding phyto. There is tons of micro life, and like yours along with the feeding came some cyano, as well as brown algae film on the glass which when cleaned would come back in a couple days of not cleaning. PO4 always undetectable, and I was maintaining NO3 at 5ppm with dosing for macro growth. Now I've quit dosing, and cut back on the feeding alittle and the cyano has gone, and the brown film doesnt come back as fast. Surprisingly my macro growth has actually sped up with the lack of dosing. I am now picking up the feeding without the dosing to see what happens, and the cyano and brown film are back. I've also read Eric B's articles, and if I remember correctly his claim is that the algae will come at first but once the micro life catches up the algae will fall back and things will stabilize. I dont think I would turn my skimmer off. I have a lifereef VS3 72", and it keeps the water pretty clean. Without it I think things would foul pretty quickly and perhaps get out of control. An ATS system or Ecosystem could perhaps replace it, and I would like to try these systems on a smaller scale someday.