# Placing new substrate over an old one



## eddtango (Mar 18, 2005)

I'm planning to convert an established fish only tank to a planted tank,is it possible just to "top off" the existing gravel with another substrate? Can I still re-use Eco-complete over this older gravel? I'm afraid that I might just kill off any beneficial bacteria in the existing gravel. BTW,the old gravel has some BBA.


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## trenac (Jul 16, 2004)

What I would do is leave a 1/2" layer of the old gravel then add the new gravel over the top of the old gravel.


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## bristles (Mar 7, 2006)

It might be a good idea to vacuum the gravel to get the majority of the mulm out, but not all of it as it makes a good seeding base for the bacteria. If the BBA persists I would strongly suggest you use Flourish Exel it works wonders on that nasty stuff. how much eco-complete are you going to add?


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