[quote=@rush99999]
<Snipped quote by Guardian Angel Haruki>

Out of curiosity, what encounter table were you using for these rolls?
[/quote]

[quote=@XxFellsingxX]
<Snipped quote by rush99999>

I'm assuming the section of the book which takes place in that area has like a table of "Thinks you can encounter in the water" or something like that.
[/quote]

You would think so!

The Book does have random encounter tables. But not for the lake.
But all the book provides for encounters on the lake are noncombatant bullywugs and the two merrow. 

So, there was no table. 

For me as the DM it was a quick, "[i]Ok. Depending on the roll of the d100, it'll be some size of fish. If he rolls a 90 or higher, it's going to be the two merrow. How likely is that?[/I]"

...And then somebody rolled above 90 on the percentile dice.

EDIT: (It's on Page 206. Rush rolled a 97)