Just recently i started a tank without much knowledge.
I bought all the stuff from PETSMART, 36 galon bow front aquarium with all the equipment needed for it.
Not knowing much i bought the TOP FIN gravel which is not nice at all and i don't have enough of it i guess.
Anyways i want to know how many inches of gravel do i need for a planted tank.
I'm going for the Eco Complete.
What I did in my 50 was bought about 3 bags of eco complete and mixed it with gravel from petco. First, it keeps the cost down. Second, unless you want the all black or red look (i went with the black with a pea gravel color) mixing them looks great with wood or lava rock. My suggestion for a 36 would be buy 2 bags of eco and 2 medium size gravel bags. Clean, mix them together in a bucket and lay it out. Follow some of the posts on how to properly substrate a tank ... best of luck!
Keep in mind additional substrate depth can allow your plants to be a bit closer to the source of light, all other things being equal. That can make a difference in a taller aquarium such as a 45G (24"H). Or, perhaps you don't have the best lighting at the moment for an bigger aquarium, deeper substrate might just be an inexpensive solution to what is needed for more (light) demanding plants until you can get better lighting.
Also some folks like terraced substrate so there are different levels in the aquarium. I don't have the patience (especially for a planted tank) but when it's done well it looks great.
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