If you only used a teaspoon, I would go with the total dosage Muddy recommended.
As far as the runoff on the Northern, has she gotten too dry recently? The times I've had that happen, it was because I had let the soil get too dry. When the soil gets too dry, it compacts and shrinks inside the pot. When the soil shrinks, it pulls away from the inner wall of the pot and it creates gaps for the water to flow through without having a chance to be absorbed. Also, when the pot gets moved cracks form in the compacted soil and it creates pathways for the water to run right through.
If this is the case, I've found that carefully cultivating the top 1/4" to 1/2" of your soil with a fork will do the trick. This helps the water to spread out more evenly across the top of the soil before it goes down. You can also take skinny bamboo skewers and very carefully poke some holes down into your soil at least 1" in from the inner wall of the pot.