Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
Dampen the soil pretty well.
Make hills and valleys, add rock, driftwood.
Put cap in places you will not be planting. OK to pile it up in several places.
Plant, misting the plants. Fill in the cap around the plants as you go. ( I have a hard time plating through a cap, but if it works for you, that is OK, too)
Put a plate or plastic bag over the substrate/cap and fill very slowly, allowing the water to seep in over the edge of the plastic or plate. When the water is high enough turn on the equipment. Make sure any jets of water (filter outlet, power head) are not disturbing the substrate.
This will generate the least cloudiness. Usually whatever haze there is will clear in about 24-48 hours, and is not so bad that it would cause problems for any fish. If it is too cloudy (cannot see the back of the tank) then yes, you could fill and drain.
I do something like that, sometimes.
Put damp substrate in tank. (I don't want to breathe the dust)
Pour in the water, deliberately making as much mess as I can. Jet the water in. Stir the substrate.
Drain, but move some substrate out of the way and REALLY make sure to drain 99.99% of this muddy water, all the way to the bottom of the glass.
With some substrates I will do this twice. These substrates are not filled with fertilizer.
Do not have to totally fill the tank. Half or less is fine with tall tanks, smaller tanks might need more water.
This is rinsing the substrate in place.
After all that (it really goes quickly) follow the instructions about planting BEFORE adding water.
The last tank I did that way (88 gallons, Safe-T-Sorb) I used the empty bag the substrate came in to ease the water into the tank.
I could see through the water from the minute it was filled, though I could see some haze. 24 hours later it was much clearer, had to look through an end, through the full length of the tank to see any haze, and that was gone the next day.