Hey
@Joel Armstrong - thanks for asking.
Been an interesting month (almost). As predicted by others, the PO4 level in the water column drops rapidly. Initially I was adding about 5ppm per day and within 24 hours it was back to 0.25 to 0.5
These last few days its more like 48 hours for the PO4 level to drop from 5ppm added to 1 to 2ppm.
Initially after planting I was a little worried as some of the plants did not seem "happy". But, as expected, most seem pretty happy now. Growth is atleast as good as it was before the change and possibly better.
Right now brown diatoms seem to be the flavor of the day. Will probably fade in another week.
I really should test NO3 levels more often as I really don't know how much the soil is soaking up between weekly water changes. Getting a bit of green dust algae on the glass and slow growing plant leaves. Again, I should probably adjust NO3 levels added - just need to decide which way to go, LOL