I can tell you from experience, that if you use spray sealer over a grout-covered, styrofoam (white compressed bead-type is what I used) waterfall that it will discolor shortly after the water is turned on.
I constructed my waterfall from white styrene bead-type foam sheets. I gave it a coat high-hiding water based priming paint (it contains micro-silica bits that increase the opacity, I suppose. It was safe for children, so it's safe for my critters.) and let it dry for a couple of days as I did other things.
I then gave the feature 3 coats of grout (tan colored - colored by the mfr.), letting each coat dry 24+ hrs for each. I applied acrylic paint -very, very dilute and with a spray bottle, wiping off the raised areas to simulate sun bleached rocks.
Then I found a can of craft sealant. This should help to water proof it, thought I. The dried water feature then had a semi gloss finish. I coated the water path with silicone seal and let it cure.
2 weeks later, the whole feature was covered in hundreds of white spots. Water percolated between the styrene beads, to be trapped between the sealant and the grout. To fix this, I had to repaint the whole feature using acrylic craft paints. 1 month later, there are no spots. [In retrospect, in the future I will only use closed-cell foam for water features. Then the water can't permeate to the surface of the foam from under the grout.]
TIL: Do not apply a spray sealant to foam & grout water features.
Yes
Styrofoam is a mass noun, it is already plural. It is most often encountered as an adjective - i.e. a Styrofoam mug, a Styrofoam container ... and these do not have a plural just as there is no plural for "big" in 10 big mugs or 20 big containers, we just say 10 Styrofoam mugs, 20 Styrofoam containers.
Waterfall is one of the software development life cycle model. Waterfall model has five stages.
The denser the styrofoam, the greater it's load bearing ability.
styrofoam can kill animals on earth and in the ocean. try not to use it p.s writen by 5th grader
a cup made out of styrofoam...........................................................................................................................................................................
Styrofoam... it's like polystyrene
in a factory
Yes
Small balls made of styrofoam. Craft stores sell them in various sizes.
Because styrofoam is made from the same oil base as gasoline, and has large air pockets.
usually styrofoam
Styrofoam is indeed lightweight compared to other substances from which cups are made such as clay, metal or glass.
Styrofoam is not renewable. It is plastic, made from oil, a fossil fuel. Plastics can be recycled but recycling of domestic styrofoam is often difficult as many recycling plants will not take it.
Some fiberglass and Styrofoam.
styrofoam
Styrofoam