After all I have read about cat litter I had to have a bash with it!!
I emptied the 60l planted tank I have dedicated to shrimp last weekend and used the tesco kitty litter. I just left it under the shower in a colander for 10/15 mins and that washed most of the dust off it. I guess you could wash it all day and still get some fragments coming off though. I honestly didnt have much of a perfume to mine, even at the beginning before any washing it was never strong and since it has been in the tank I have never smelled anything. I carefully poured the old tank water back in and the tank was completely clear after a couple of hours. A handful of osmocote fertiliser underneath and bob's your uncle! Lets see how the plants like it now...
The only, but major, downside is its weight.... I had a HC carpet and trying to replant this in the CL is almost impossible. I ended up breaking the HC into very small pieces and pushing 90% of each clump under the CL in order for it to stay down. As soon as you try and place a clump nearby the previous clump comes floating up!! I knew before I tried planting the HC that I should have used a dedicated sand area for it. That would be my only advise, if you are trying to obtain a carpet with a plant with shallow roots I would put a small layer of sand over it. I am sure the sand will fall through the CL over time and mostly vanish but at least it will give you a base in which to hold the roots..
A fully inert, good looking, high cec, long lasting substrate for £3 !!!
