IMO, Fleets is the easiest and cheapest way to dose Phosphates.
As mentioned before, I don't know your plant mass, so I would start with 4 drops, give it an hour or so, and test adding increments of 2 drops to reach the desired content.
That first trip to the register with an Enema in hand is always dicey.......just tell the lady that it's for dosing a planted tank.......she won't believe you, but what the heck,
at least you tried
.
Len
As mentioned before, I don't know your plant mass, so I would start with 4 drops, give it an hour or so, and test adding increments of 2 drops to reach the desired content.
That first trip to the register with an Enema in hand is always dicey.......just tell the lady that it's for dosing a planted tank.......she won't believe you, but what the heck,
at least you tried
Len