Now, to answer a few questions.
Here is a very crude diagram of the plumbing circuits.
1. 4" bottom drain in the shallow end (1.5-2' deep)
2. 4" bottom drain in the deep end (3-4' deep)
3. Savio 16" skimmer, modified with 3" bottom drain looping under pond floor via 3" flex pvc to hole where bottom drains are currently popping out.
4. Sequence 4200 GPH pump
5. Savio 31" Filterfalls
6. Undergravel filter in bog
7. Sequence 4200 GPH pump
We may also add in some TPRs in the shallow end to direct debris toward the bottom drains. Future filtration such as a sieve from the bottom drains to a bead type filter.
I hope the bog will eventually look like this photo from a Helen Nash book. Just ordered two lotus from Craig for delivery next week!