Question 1. What time of the year should I have the water tested again?

Now. That will give you a baseline when the majority of P isn't bound up in phytoplankton or plants. Test for alkalinity, N and P. BUT without alkalinity that is a minimum of 40 ppm, any nutrients won't be able to be utilized if the alkalinity isn't at least that high

Question 2. Is liming a pond with such a flow through a waste of money?

You never stated how much flow through the pond had. How much does it have?

Question 3. Why have I not witnessed a plankton bloom?

Possibly see the answer for question #1.

Question 4. Can a pond with flow through not be fertilized?

Sure, but if the alkalinity isn't over 40 ppm, then you will keep seeing the results you are having.

Question 5. What am I missing?

How old is the pond?

What is the RW of the bass that are in there now, and how big (in length) are the larger LMB now? How does the RW compare from this year to the previous years? Does the RW of the LMB stay consistent throughout the different year classes of LMB or does the RW vary greatly between the year classes? How is the BG population, when you say abundance, how many do you estimate and what are the size ranges? Are you seeing plentiful BG of all age classes? How many LMB are you harvesting every year (in pounds)? By adding 6" F1's, they could become food for the LMB that are in there now if there are LMB in there over 18"..... What was the reason why the fishery guy didn't want to add straight Northern or straight Florida strain LMB?

When you say abundant, how abundant? To get LMB to grow quickly, you want to have fish that are between 1/3 and 1/4 the length of the LMB in there, and at a ratio of 2,000:1 to 3,000:1 for the fastest growth. (forage fish to LMB)

If you were to estimate the amount of structure and cover in the pond in surface acres, how much is there? i.e 1/4 acre, 1/2 acre, etc. Is the cover made of things that have different sizes of openings in there or are they all one thing (i.e . brush piles).