These have done their job well , its only been a few weeks but it seems to be doing what its supposed to!
I had no issues with them flozting or any trouble sticking them in the gravel i did get some pots for the root feeding plants i have because i have an undergravel filter but well worth it cause my plants r growing a lot by the day .
These root tabs have to be placed directly on the bottom of the aquarium or they'll float to the top. Be sure to get it right the first time or they'll start to come apart. This is easy to use.