Hi Gary.

I'm sure others will give you a better answer but this is just based on my experience. I've grown the aquarium plants ... the Vals., Crypts, Lace Plants, Banana Plants, Sword Plants... all that good stuff and more. I've always removed them from their pots when I got them home, rinsed the plants thoroughly roots and all to remove any snails, leaches, eggs... and planted them directly into the gravel.

Right now we just have the 55 gal. freshwater tank with an undergravel filter and the uplift tubes are attached to a pair of outside filter boxes. The roots quickly go through the filter plate and are fed by the organic material the filter draws down. The plants grow quickly send out their runners or however they grow and cover the bottom of the tank and thrive.

At least 4 times a year they need to be thinned out to make room for the fish to swim as well as open up some of the filter plate again. But in reality I think the plants are doing more of the water purification than the mechanical filtration on the outside of the tank.

Will you have some kind of mechanical filtration system? Fish? Maybe you could experiment with a few mediums? Have several large containers with various medium types and see what does best? Of course different plant species may prefer different medium too.

Or divide up your pond. Make an area in one part of your pond with soil covered by gravel. With some low partitions that could easily be removed, another area has fine sand, "cactus soil" or gravel. Maybe a cocoa mat could be used too?

I don't know what the soil or mat would do to your pH and other water chemistries. That would be very important if you have any kind of fish with your plants.

Sounds like a great project. Photos please if you have time.

C3D

Hi
This pool is 5x10 feet x3 deep. Above ground I added a 2x8 foot window ,new filtration system,automatic water chager and heating system. The only plant I'm going to return is a waterlily. i have grown most every type of aquarium plant but only in aquariums or in pots in the small pond. This has always been limited due to the winter but since I now have a heater and can be viewed below water
I'm thinking giant aquarium rather than pond lol
I thought it would be interesting to plant star grass and red temple plant maybe in geometric patterns just for fun. Obviously there will be maintenence as star grass easily gets overshadowed and constant clipping to remain in a mat formm. Though I would like to have it on the entire bottom I don't see that happening lol Would be a nightmare to keep up lol. The 3x 4 pan should give enough area to make a pattern and could always be removed even lifted up for clipping. Star grass needs intense light and rich media
to really give the carpet look but I'm hesitant to add that much dirt to the pool lol. The other plants. swords ,Crypts and whatever will be kept in clay pots in groups . I don't have near enough plants to landscapr this large an area so this will be an ongoing project for a long time. Just thought it woyld be fun to not only grow the mat formers but arrange them in geometric patterns when viewed from above. Sort of a formal planting schemme but underwater lol. if it works I can expand if it not much easier to remove .lol I'm thinking peat and clay but feel it will not be rich enough. have had wonderful results with top soil in aquariums but requires weeks to stabilize the water. Another problem is that I had to use the hose for the majority of the water. and only have 200 gallons of rainwater so this will have to be adjusted over time also.
I'm thinking of maintaining either Discus or Angels but the plants come first besides I don't have the necessary water conditions . Thanks for the help gary