If you dont understand any of this, use this tool
http://tat2mikki0.tripod.com/
Note: Sometimes for 3 color beds, when a spot changes to blue it will appear white. To fix up the colors, redraw the screen by hitting scroll-lock
Solving any Oyster Bed
Once you have learned the basics of oyster beds (see
Catching Oysters for the basics) you may solve any bed using the fool-proof method outlined on this page. This method can be used for any oyster bed that currently exists in the game (1 color 5x5 and 1,2 and 3 color 6x6 beds), with only small differences depending on the type of bed. Oyster beds are most easily done in the double-F8 view; I will refer to north, south, east and west as up, down, right and left respectively.
Step 1: Chasing
To begin with, our goal is to eliminate all of the lights(bubbles) except for those on the very bottom row. This is done through a method known as chasing. This step is the same for all types of oyster beds. In order to chase the lights to the bottom row, start in the second row from the top and for each light in the top-most row, dive in the tile directly beneath it until it has disappeared (if it is a multicolor bed, you may have to dive multiple times). Repeat this for every light in the top row until they are all gone. Then move down to row 3 and repeat the chasing process (catching on now?) repeat the chasing until you are left with only lights in the bottom row. (If you are very lucky, there may be no lights left in the bottom row, in which case you're done. Otherwise, continue reading.) Now, on to step 2. For 6x6 beds go to 2a and for 5x5 go to 2b.
Step 2a: Adding (6x6)
Now that you have eliminated all of the lights except those on the bottom row, you need to figure out how to eliminate those. This is done by diving in a certain combination of tiles in the very top row and then chasing them down again. First we need to figure out which combination of tiles to dive in.
The tables below list the combinations of tiles you would have to dive into in the top row in order to have the same effect as diving once in a tile in the bottom row *without* affecting the surrounding tiles as you would if you were to simply dive in that tile. Lights in the bottom row are labelled a to f in order from left to right, and lights in the top row are labelled A to F, also from left to right.
When you have finished chasing you will have a combination of lights at the bottom. Take a look at which ones are lit up. For each light see how many times you would have to dive on it to turn that one off (this is color dependant: white 1, green 2, blue 3). Now one light at a time look up the light in the appropriate table below. Multiply the number of dives by the numbers in the columns in that row. Do the same for the other lights. Now, add up the numbers in each column. For each column the result is how many times you have to dive in that spot in the top row during step 3.
As you may have noticed, if you press a light a certain number of times, it will have no effect. That number is the number of colors in the oyster bed plus one. So, look to your totals for diving in the top row, any numbers that you have right now that are the number of colors plus one or higher, you can subtract the number of colors plus one from unitl you are no longer able to without going negative. (ie if you have 9F in a 3-color bed, you can subtract 4 twice to get 1, meaning you only have to dive in F once.)
1-color
| | A | B | C | D | E | F |
| a | 1 | 0 | 1 | 0 | 0 | 0 |
| b | 0 | 0 | 0 | 1 | 0 | 0 |
| c | 1 | 0 | 0 | 0 | 1 | 0 |
| d | 0 | 1 | 0 | 0 | 0 | 1 |
| e | 0 | 0 | 1 | 0 | 0 | 0 |
| f | 0 | 0 | 0 | 1 | 0 | 1 |
2-color
| | A | B | C | D | E | F |
| a | 0 | 2 | 2 | 0 | 1 | 1 |
| b | 2 | 2 | 2 | 0 | 1 | 1 |
| c | 2 | 2 | 0 | 0 | 0 | 0 |
| d | 0 | 0 | 0 | 0 | 2 | 2 |
| e | 1 | 1 | 0 | 2 | 2 | 2 |
| f | 1 | 1 | 0 | 2 | 2 | 0 |
3-color
| | A | B | C | D | E | F |
| a | 1 | 2 | 1 | 2 | 0 | 0 |
| b | 2 | 2 | 0 | 1 | 2 | 0 |
| c | 1 | 0 | 2 | 0 | 1 | 2 |
| d | 2 | 1 | 0 | 2 | 0 | 1 |
| e | 0 | 2 | 1 | 0 | 2 | 2 |
| f | 0 | 0 | 2 | 1 | 2 | 1 |
Example
In a 3-color bed, I have chased down and there remains a light in the second column (b) which I have to activate 3 times to turn off, and one in the right-most column (f) which I have to activate once. So, I multiply the b row in the 3-color table by 3 to get 6A,6B,0C,3D,6E,0F and then add the numbers in the f-row to get 6A,6B,2C,4D,8E,1F. Then, since it is a 3-color bed, I can subtract 4 from any numbers that are 4 or higher, so I do that to get 2A,2B,2C,0D,0E,1F. That means that in Step 3, I have to dive in the top row in the A column twice, the B column twice, the C column twice and the F column once.
Step 2b: Solution Lookup (5x5)
Unfortunately, not all possible positions of a 5x5 bed are solvable. In fact, only 1/4 of all possible positions are (but don't fear, you won't find an unsolvable position in the game). As a result, it's not possible to make the same sort of table for a 5x5 as above for the 6x6 configurations. On the bright side, there are only 8 possible configurations once you have chased down anyway, only 7 if you dont include the position with all of the lights off, so it's easy to list them and tell you the solutions for each. Simply lookup your bottom row configuration below, and move on to step 3 with the dive pattern on the right side.(small letters indicate bottom row lights on, capital letters indicate which top row space to dive into during step 3)
| a,b,c | B |
| a,b,d,e | C |
| a,c,d | E |
| a,e | A,B |
| b,c,e | A |
| b,d | A,D |
| c,d,e | D |
Step 3: Diving in the top row, and rechasing
Now that you have figured out which tiles you need to dive into in the top row and how many times, you can go ahead and finish the puzzle using the same procedure outlined in step 1 to chase the lights down to the bottom, except this time, you should be left with no lights turned on. Congratulations!
If there are still lights left, you most likely made a mistake in step 2, but all you need to do is do that step over again with the new configuration. Do that, and repeat step 3 and you should be done. If you are still having trouble, feel free to contact me (Nonym) for help if I am on the game.