i have a deka marine master dc31 house battery. i checked the fluid levels & noticed it was down about an 1". i added distilled water to each section and filled it to about 1/4"-1/2" to the top. yesterday morning i noticed a dried puddle under the battery. i had spilt some water filling the battery and figured it was from that. last night i noticed there was a smaller dried spot in the new location i had put the battery. then i noticed a small opening on the top side of the battery with a drop of water on it. i rocked the battery back and forth and noticed a couple of drops come out. this morning, there was a smaller area of water under the battery so whatever is coming out is lessening. could i have overfilled the battery? by refilling it, when the new water mixes with the existing acid, does it expand?