This forum has been incredible for advice as I have been constructing the "dream layout." Finally getting to scenery - my least skilled activity. Have used learning kits from Woodland Scenics and Scenic Express to get acquainted with materials and techniques. Here's a photo of kits for pond and mountain. Grandkids love it!
It was only 3 years ago that I requested and received guidance on the depth of the harbor scene!! Now finally ready to pour the water effects. I attached a photo of the area, with base and embankments installed ready for the pour. The area is about 6' sq. Decided to go with Envirotex product and have half gallon each of resin and hardener. Have water color tints for Moss Green and Olive Drab. Did several test pours with grandson to see what the colors look like and get acquainted with process (see photo). Will do a few more to confirm color choice. 
I would appreciate your expert advice on the following:
1. Any idea how much product to produce? Some formulas I have seen suggest about a half gallon for 1/4".
2. Should I do two pours of about 1/8" each?
3. I intend to tint the product a shade of green. If I do 2 pours, should 1st layer be a bit darker than 2nd?
4. Any suggestions for container to mix and pour? Hard to find straight walled and flat bottom container for estimated about product.
5. Essential to be vigilant in doing a 2 cup mixing process? I see both pro and con comments on various forums from those who have harbor scenes.
Many thanks in advance,
Michael
