That's a very interesting video not to mention the speakers was pretty funny

Definitely one of the better speakers....some are so dry lol

Thanks for the video. It kind of opens your eyes to how little we know about what the corals truly need. Many of the top experts in the field have been running their reef tanks with much higher phosphates and nitrates then most of us hobbyist reefers do and had great success with those numbers. They have also had long term stability that few achieve.

I purchased some KH2PO4 yesterday and added it to my tank. I used a calculator that MYKA sent me to figure out how much I needed to add. I ended up adding 1ml of a solution of 1gram of KH2PO4 to 250mls of ro water. My phosphates are now at .02ppm.

I added .5ml of the solution today. I want to get my phosphates to .03 with my nitrates at 1.5ppm. Try to maintain that Redford ratio mentioned in the video. I will take this really slow and try to stabilize my tank to settle my corals down. I am happy I finally have measurable phosphates.

Keep in mind that the Redfield Ratio is the uptake ratio of phytoplankton. It is not the ratio in the ocean, nor is it the uptake ratio of corals. It is a good guideline to use though, just as long as you understand it. Really all the Redfield Ratio is doing is putting in perspective how tiny of an amount of PO4 you need in comparison to NO3.

FWIW, 1.5 ppm NO3 is 50x PO4 at 0.03 ppm. Redfield Ratio is 16x. :)

The way I see it is that no matter how hard we try to mimic nature, we just can't do it nearly as well, so we use fertilizers (literally haha) to try to supplement the corals. It works in many cases, but not all. It depends what's missing or lacking in your own system. There are examples all over the map of tanks with high nutrients and SWEET Acros, and there are examples of SWEET Acros in immeasurable amounts of nutrients. Everyone's tank is different, and this may not be your magic potion.

The ratio is actually 33 to 1 because phosphate is 31% phosphorus by weight and nitrate is 21% nitrogen by weight.

I started with no nitrates and had unhealthy corals I dropped the phosphates to 0 and have very unhealthy corals.

For now I want to get the phosphates to .03ppm and stabilize it for a while. My nitrates for now seem to want to stay at 1.5ppm

I tested my phosphates this morning and they are back down to 0 so I added another 1ml of the solution and re test it tonight.

Yeah you're right about that, but it still doesn't matter. :)

Read through this discussion. http://www.reefcentral.com/forums/sh....php?t=2109768

Thanks for the input. I had already read that thread. I don't believe the magic answer is the Redfield ratio, however it may be a good place to start. Seeing as I am currently manually adding both nitrate and phosphate or else I will bottom out I have to shoot for some value and not blindly add both solutions. I really just want to create some stability so my corals can recover.

I tested again tonight and my phosphates are still 0 so I added another 1ml of the phosphate solution (want to take it slow). What I did notice which I am happy about is the nitrates have began to drop a bit and the alkalinity and the calcium have started to drop again as well. It has been a week since my tank has used any calcium and alkalinity so this may be good. Although it is just likely the coralline algae has kicked back in.

Yeah, me too. I'm not seeing any difference in the corals yet. I dosed NO3 up to 5 ppm, and PO4 I add 0.02 ppm every evening which the Hanna ULR Checker is able to confirm. The following morning PO4 is still 0.02 ppm, but by evening the green cyano has sucked it all out of the tank, and I'm back at 0 ppb. I'm hoping the cyano cycles out, and the corals start using it instead. I'm not sure it's the magic concoction for my tank yet, but it's too early to tell for sure.

Tank update:
For several days I have managed to maintain acceptable levels of phosphate and nitrates, although once my phosphate started coming up my nitrates started heading down. So I am adding daily doses of both phosphates and nitrates.

Too early to tell full damage to corals. Some of the harder hit corals are starting to extend their polyps so I am hopeful that the worse is behind me. "Fingers crossed, touch wood".

There is definitely a direct relationship between nitrates and phosphates. Each one controls the other when running low levels in a nutrient low reef tank.

From my experience when nitrate is the limiting nutrient (0 nitrate), poor colours and slow growth rate.
When phosphate is the limiting nutrient and has truly bottomed out bad things happen, much worse then low nitrates.

It is funny how some acros were not really impacted and others were devastated. Once I have a full grasp on the impacts I will provide a list of the corals and how they were affected in my tank under my adverse conditions.

Even though I suffered some serious setbacks I consider this experiment a success. Remember in the first post I said this was an experiment and I have kept all the data. I have learned far more than if I was just blindly lucky and had succeeded because I wouldn't have known why I succeeded.

I have had the same experiences.