first time using program logic, help with skimmer delay please

Hello- This is my first time using program logic and I need a little help. I think I have things working, but I ran into an error I can't explain.

I am trying to program a few different controls for my skimmer and return pump
Feed 1 - Pump off 10 min, skimmer off 15
Feed 2 - pump off 10 min, skimmer off 4 hr
Maint 1 - Pump and skimmer off; then skimmer delay 5 min after return pump on
Float sensor to monitor sump level and turn off skimmer if to high

Here was my first attempt

Control Circuit 2 - Leakage detection - input 3

Program logic
Gate 1 - Delayed on - Filter 1 - 300s
Gate 2 - Delayed on - Filter 2 - 14400s
Gate 3 - Delayed off - maintenance 1
Gate 4 - PL1 AND PL2
Gate 5 - PL4 AND PL3(INVERT)
Gate 6 - PL5 AND Fill water 2

Gate 7 - Filter 1 AND Filter 2
Gate 8 - PL7 OR Maintenance 1

Sockets

Return pump - PL8
Skimmer - PL6


The Return pump seemed to function correct, but the skimmer did not. After some troubleshooting I realized no matter what I put in gate 2 I couldnt get the socket to function properly; so I tried the same code but instead of using gate 2, I used gate 10. For some reason, this seemed to fix the problem. Anyone have any ideas why this would happen? Also, if anyone has a more simple method of doing this please let me know.

New Code that seems to work:

Control Circuit 2 - Leakage detection - input 3

Program logic
Gate 1 - Delayed on - Filter 1 - 300s

Gate 3 - Delayed off - maintenance 1
Gate 4 - PL1 AND PL10
Gate 5 - PL4 AND PL3(INVERT)
Gate 6 - PL5 AND Fill water 2

Gate 7 - Filter 1 AND Filter 2
Gate 8 - PL7 OR Maintenance 1

Gate 10 - Delayed on - Filter 2 - 14400s

Sockets

Return pump - PL8
Skimmer - PL6