How about this insted of gravel?

Hmm, I don't know about the eco complete, but I have a 55g planted now with Schultz Aquatic Soil on the bottom layer of substrate and sand on the top and it works out well. The Schultz stuff needs to be rinsed, but I think it's a lot cheaper than some of the other things out there. I paid $6-7 for a 10lb bag at home depot.
 
I've heard nothing but good about eco complete- known two people who have used it and raved. There's no washing involved, it's nice and dark- they have a specific mix for african cichlids too which will keep the pH high and well buffered and give you the gH and trace minerals without having to add anything else. It is a bit on the pricy side as compared to Schultz Aquasoil (the only reason I chose Aquasoil over Eco complete- it was about 2.5x the cost at my LFS vs. Lowe's).
 
You could also post this in the planted forum, folks there will have lots of opinions/info on substrates for planted tanks.
I haven't heard anything bad about Eco-complete, FWIW.
 
I bought a bag of schultz aquatic plant soil, but have yet to try it out. I was going to make that the only substrate in the tank, would this be okay or should there be something on top, like sand? Thanks
 
You can use it as the only soil. It is on the light side though, so you may want to mix it with some normal gravel about the same color if you can, just to help weigh down the plants.
 
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