Had to look up pami pebbles, never heard of them. If kids are just walking around or playing in it I can't see where it would matter. The difference comes if they're potentially jumping or falling into it. There's a table that breaks down the various materials (link below) Anecdotally, I'm not a fan of pea gravel for kids' play areas. We had a fancypants play area built when I was in elementary school and the flooring material was 5" of pea gravel. One got good at surreptitiously picking it out of one's legs during class post-recess to avoid getting sent to the nurse's office. No kid likes hydrogen peroxide. Here is a link that might be useful: fall table, more info

I used crushed gravel as the floor in my 10x18 greenhouse originally. My thoughts were that it would provide good drainage and be tidy. However after the first year I discovered I was tracking a good deal of it out the door stuck to my boots, either in the tread or in the dirt on my boots from mucking about in the gardens. I approached a landscaping company at the end of the season and made a deal to buy up small lots of leftover paving bricks. They wanted to get rid of them because the colours wouldn't exactly match the new stuff coming in and I was happy to get a great price. It only took a couple hours to lay them as a floor in the greenhouse and I arranged them in such a manner that you don't notice any colour differences. They make a great floor, sturdy under foot, can be swept or water sprayed clean and you can wet down if you want more humidity. As for placement, it is best to have a southern exposure for optimum light but you will want to have lots of venting and a shade cloth as summer approaches to keep the heat down. You can buy actual "shade cloth" but I had a spun polyester rowcover material-very thin and white-so I used that. Just tacked it to the southern ceiling of my greenhouse and it has worked perfectly. I use cheap bamboo blinds in the southern wall of windows. Kind of ironic that we spend all this money to catch the sun then have to shade the plants from so much of it. I also have an automatic roof vent and many windows and doors I can leave open. I've arranged a system of propping windows open and then using bungee cords to hold them in place so that the wind can't catch them and rip things off or break glass. (I used a wheelbarrow to prop a door open and lost a glass window on the FIRST day my greenhouse was finished to a big gust of wind that put the handle through the window!)

I finally found a forum and a thread I could post to! My husband and I got a Rion 8x8 for Christmas 2004. It took us two days in Texas to get it assembled. We dug the trench like it says, filled it with sacked rocks to make it all level, and then put down the base. After we completed the GH, we put rocks on the insides of the base to hold it down. It has two vents in the top and we are going to put a fan in this spring. We just used a small ceramic heater for the very cold nights (18-25) and most of the time, heat is the problem, not the cold. For a floor, we used wood chips. We were fortunate to go to an Organic Gardening show between the time we put it together and when we did the floor. Malcolm Beck, the guru, said that using wood chips is ideal because as they break down, they give off carbon which the plants like. He has been doing this for years with no bugs, he claims. We thought the Rion was very easy to assemble after we got the ground ready for the base, just like the ads say. Mounting the vent windows was a little tricky but we got smart and did the weather stripping on a very warm day which made that part a lot easier. It did take two of us 4 hours to put that on the entire house. We have a lot to learn but we are having fun. A couple of times we had to remind each other that "this is a hobby, this is fun". My husband got his garage back that used to be more like a jungle. We used some plastic shelving that he had bought for garage storage for benches so they line either side and are two deep. I have great pics and just as soon as I learn how to post them I will.

Top dressings are great. I like pea gravel, crushed granite (grit for roofing), screened decomposed granite, red lava (scoria) of different sizes. I imagine black scoria would look nice if used sparingly. Coarse silica sand looks good too. I can't bring myself to buy little baggies of material for $2 or $5 at club sales -- I prefer to buy by the cubic foot at least. One of the most important roles of top dressing is to mechanically stabilize the base of the plant. Another role for top dressing... if you use something inorganic like pumice, you can cover the base of the plant (eg, to cover flaws or make it appear less leggy) without promoting rot. Effectively you're just raising the level of the soil -- risky with some plants unless you use the right materials. Take care and pay attention to your plants. I think I killed a couple plants by covering a grower's organic-rich mix with a top dressing that was too heavy (fine crushed granite). I think the crushed rock retained too much moisture and rotted the plants' roots (small Dorstenia gigas and Aloe pronkii, ouch!). When I bought replacement plants (addict!), I tipped out most of the grower's organic-rich mix and topped with small pumice instead of fine rock. Crossing my fingers, this should work better. Wish me luck!