[Wet Thumb Forum]-Sagittaria pusilla in a soil based substrate

[aquaticscapes]

I am interested in setting up a shallow hydroponics tray with Sagittaria Pusilla. Would I be better off using conditioned soil from the pond, I think I read in the Ecology of The Planted Aquarium Book that 6 weeks is optimum for the soil to be optimized for growth. Or could I start with new soil? I am planning to use a powerhead on slow as well and grow them submerged. I will then use the covers provided with the trays to keep evaporation down and of course hanging lights. Thank you, Don M.

[aquaticscapes]

I am interested in setting up a shallow hydroponics tray with Sagittaria Pusilla. Would I be better off using conditioned soil from the pond, I think I read in the Ecology of The Planted Aquarium Book that 6 weeks is optimum for the soil to be optimized for growth. Or could I start with new soil? I am planning to use a powerhead on slow as well and grow them submerged. I will then use the covers provided with the trays to keep evaporation down and of course hanging lights. Thank you, Don M.

[dwalstad]

Dear Don,

Welcome to the El Natural forum!

I'm not sure whether using your old pond soil (submerged already) will help that much. That's because when you dig that soil out of the pond (whew!), you'll be introducing oxygen and stimulating the bacteria. So you're basically starting over again.

For my tanks and despite chart on p. 131 in my book, I've always used soil right out of the garden (or bag). Main things (for most aquariums) is that the soil not be fertilized with NPK, and that the soil layer not be too thick.

If you're growing the Sagittaria emergent, they should do well with any soil. The soil can be more fertile, since emergent plants are able to grow much better than submerged forms of same species. I would recommend testing this out by setting up small trays with different soils.

Also, since yours is a hydroponic/nursery situation, you may not want to use soil. Soil contains inhibitors to plant growth (often excessive metals, anaerobic pockets, etc). If I wanted maximum growth from hydroponic cultures, I would use standard hydroponic techniques, that is, clean nutrient solutions, rock wool (not soil) for roots, good lighting, emersed growth, etc.

[aquaticscapes]

Thank you for the welcome! I initially used rock wool with a nutrient solution, but cut a slit in the top to the tray to accommodate a small powerhead to circulate the water. Unfortunately this compromised the total humidity and the plant leaves started to whither on some plants. Since the post, I decided to try a light aquatic substrate mixed with laterite and plant the Pusilla with the crowns and part of the plant submerged. I will insert an air hose from a pump and CO2 gas hose in the water column and then seal it with Saran wrap to prevent humidity loss. Then enough oxygen and CO2 will be present to facilitate growth. I also have a reptile heating mat sandwiched between glass under the tray to keep the water warm. Hopefully this will be successful. Don M.