I'm using the top half of a laundry basket. I actually bought it for the bottom half - to plant some waterlilies in. It works well but is rather unsightly. It's dark green, not black. I plan to take it out once the water hyacinth clumps itself together.

Maybe a styrofoam form for making wreaths and flower arrangements? I think they come in dark gray as well as green,

There must be some sort of round black plastic "thing' in Walmart or a Dollar Store that you could use. I'd avoid the tire tube but I don't know for sure taht there is anything toxic about them

I tried bicycle tire tubes. Won't stay inflated.. Go to Lowe's or similar store, plumbing section. Get a short 2 or 3 ft piece of black or clear tubing about 1 inch size will do. Also get a connector. Make a small "hula-hoop" or ring. Glenda

Google: floating flora island by Nycon. A number of companies carry these. They are a cone-shaped net with a loop at the point of the cone, which is under water. I've attached marine-quality string to the loop and a brick to the other end so they stay put in the water. My nets are 3 feet in diameter. Personally, I don't think the 2 ft diameter ones are worth it unless you have a small pond. I have used these to contain my hyacinth for 3 going on 4 summers. They may seem pricy, but I can vouch that they are very sturdy and will give you MANY YEARS of use. (Mine have not deteriorated in any way!)

The picture, below, was taken in the early part of last summer. By mid/late summer, they are billowing with hyacinth and you can't see the floating rings at all---looks really natural.
As a bonus for those with heron problems---once my lillies and hyacinth start to spread, as in the picture, below, I can take off the netting covering my entire pond as these floating nets have deterred herons. (The pond is also 40 in deep in the middle with some hiding places for the koi.)

{{gwi:193719}}

I will chime in here...

I used pipe insulation last fall to create a fish feeding ring. This is the black foam tube with a lengthwise slit used to wrap around pipes in your house. It comes 6' long (and 4' too, I think) and you can just make a circle and use black electrical tape to connect it (hubby is an electrician - black electrical tape gets used ALOT around here :). You could just connect as many as you need to make as big a circle as you want, and I even used the tape to make a "leash" to anchor the ring. I've also used these to make floating planters. They work great, they blend in to the pond, and they're relatively cheap!

The water hyacinth I ordered this spring are in a bucket on the back porch right now because it simply REFUSES to stay above 60 degrees around here. . . sigh.

Jill

I bought this floating hoop that is called a fish viewer but also used to keep floating plants togeter.

Here is a link that might be useful: The Water Garden Store

If you just want to confine the plants to one end of the pond, run a piece of monofilament fihing line (or weed-wacker trimmer line) between two sides of your pond. Keep it tight and the hyacinth will stay on one side and you'll have clear surface on the other. And its not too visually obvious..john

I used old water tubing and taped the ends together to make a circle...tossed it in and floated the plants in that...used a piece of dental floss to tie it close to the edge.