Nutrient Levels in Elevated Elements Experiment

[Ibn]

Was the nutrient levels measured in the control and experiment tanks during the duration of the test? Curious to see what those levels were since there's obvious signs of algae in the experiment frags but not on the control frags in the video.

 

[randyBRS]

Was the nutrient levels measured in the control and experiment tanks during the duration of the test? Curious to see what those levels were since there's obvious signs of algae in the experiment frags but not on the control frags in the video.

I'll have to quote Ryan's comment from the video thread:

"We did not track nitrate or phosphate. After many discussions, we decided it was better to manage nitrogen and phosphorus input rather than track accumulation. Aaron was meticulous about the amount the number of pellets added each day.
I think monitoring the nutrient levels in the water could also be misconstrued in a variety of ways. Many reefers might assume higher or lower levels performed better but if you manage input well the higher levels probably means slower uptake. There are also a variety of other variables like the uptake by algae or organisms. In the end adding more info and data points can cloud the results unnecessarily unless you are showing them for a distinct reason and know how to interpret them. In this case, it just seemed more valuable to test one specific thing and not add in unnecessary complications. To that note, I do not see a world where we do not test how corals respond to various levels of nutrients as well, but in that case at fixed major element levels."

 

[Ibn]

I can see the point about managing nitrogen and phosphorus input by adding a specific amount of pellets into each tank daily, but that doesn't mean that they shouldn't be measured. Anyone that has seen the video will see that there's algae on the experiment frags, but none on the control frags. What's contributing to the algae or lack of algae in the tanks if the input was controlled?

One of the observation points that Randy made in the video was the fact that the biofauna in the experiment tanks was higher than the control tank. Running a lean tank versus a rich tank, nutrient wise, will contribute to that.

Overall, what I'm interested in seeing is what the alk levels was relative to the nutrient levels. I'm curious to know if the tanks were leaner (nutrients) in the control tanks versus the experiment tanks since I've never been able to run alk above 9 with ULNS tanks and you guys are above that in the experiment tanks.