Changes in lighting are exciting .. .. to us and all the photosynthetic lifeforms in the tank.
Even if the nutrients ( nitrates, phosphates and other organic compounds ) stay the same ..... once you change the lighting by either increasing or decreasing ..... the balance can change.
More or less lighting in intensity and duration will affect the microscopic diatoms and microalgaes.
Gas exchanges could possibly change as well .. although I don't know for sure.
That's about all I can think of regarding a change in lighting.
When we have make changes - stuff can happen.
New 135 gallon tank.
New saltwater.
Old saltwater.
New sand.
Exisiting sand from 55.
Existing live rock from 55.
New live rock too.
Change in lighting both intensity and possibly duration.
That's a lot of changes
Sort of like a new tank with some existing stuff from the 55.
Disrupting the 55's sandbed .. and adding it to the 135 may be contributing to the diatom outbreak as well.
I've never done that before - so I'm just making a comment.
Oh yeah .. a mixed resin bed is how most DI units work.
Two different resins in the system.
One resin attracts positively charged ions.
One resin attracts negatively charged ions.
As an example:
If you ran some table salt saltwater Na+Cl- and H2O through a mixed deionized bed, the Na+ cation would be attracted and held by one resin.
The Cl- anion would be attraced and held by the other resin.
The H2O would pass though the resins and be considered deionized.
Eventually - both resins become exhausted and can no longer attract the + or - ions. The resin is spent.
It must either be tossed out - or recharged.
