P load calibriation - accounting for algal P

[Hector Fajardo]

Hi SWAT community, 

I'm trying to simulate phosphorus (P) loads,  and I'm not sure when to account for P concentrated in algae. 

Should algal P be accounted for total phosphorus (TP) if the water quality algorithm (QUAL2E) is on (IWQ.bsn=1)? At the same time should algal P be ignored if the QUAL2E is off (IWQ=0) even though algae (chlorophyll a) is still simulated? 

I've looked at these past conversations (Chlorophyll a modeling, Nutrient transport calibration, Phosphorus subbasin - reach) but it still confusing to me.

Attached you will find diagrams of both P forms and Chlorophyll routed in two sub-basins of the model, as an example.

Lastly, does someone know the "seed" or "starting" chlorophyll concentration used in SWAT (QUAL2E)?  

Thanks in advance.