Phosphate dropping after tank transfer

[mp2022]

My phosphate is plummeting in my “new” system and I am trying to figure out why. I recently transferred my 48 gallon 1.5 year old system to a 125 gallon system. I was dosing nitrate in the old system, and had needed to dose phosphate at one point but hadn’t in a while with phosphate in the 0.05-0.1 range on average (probably stopped dosing phosphate 6 months ago). So overall my old system prior to transfer fluctuated between good nutrient levels to low nutrients requiring dosing.

My new system has only live rock (only 10lb of which was new to the system - the rest had been in the previous system) and some sand from old system. The only other new additions to the system following the transfer were 100lb of tropic Eden live reef flakes, some live sand from my LFS, and a hippo tang.

I have no skimmer, no refugium, and only filter socks that I had installed to catch some silt from the reef flakes when I first added it.

I am currently dosing nitrate, and will restart the phosphate dosing, but any insights on why the phosphates have dropped to 0 so quickly after not needing to dose the system for probably a good 6 months? Could the Reef flakes be absorbing some of the phosphates in the system?

Kind of a vague question, so thanks.

 

[EnterName]

A new tank offers a lot of surface area that has not been claimed by bacteria and algae yet. It's possible that this allowed for increased bacteria growth an reduced phosphate levels in the process.

New substrate or rock can also adsorb quite a lot of phosphate at first when it isn't already saturated.

I think (not entirely sure) phosphate can also bind to new glass (more specific silanol groups in the glass or trace elements), but I'm not sure if this has a significant effect here as well.