Fertiliser Substrate under gravel substrate

[mwe_ch]

Hi,

Is it possible to add plant substrate (not top gravel) to a tank after it's already set up? I added some to my small 40l tank which already had water, and the water was full of brown sediment for 2 weeks. Luckily it's just in the setting up phase, but I didn't want to remove the water to stall the cycle.

In any event, I plan on adding more plants to my 230l tank and might raise the gravel level on one side and add plants there, and if I do, I'd like to add some substrate to help fertilise the added plants.

Is there any way to do this? I am only in the preliminary thinking phase so haven't googled yet for ideas, I just want a quick answer here first before I start any major research.

Thanks in advance,

 

[Crepe]

Yes that's fine. But you're best off just replacing all the substrate with eco-complete or flourite if you're going to do it anyways. But in the end if you're just adding a few plants or stem plants it won't be worth your time or money.

 

[mwe_ch]

you're best off just replacing all the substrate with eco-complete or flourite

Thanks for the advice. I'll look into European (I'm in Switzerland) equivalents. For now I've added a bit of coarse gravel all over and terraced it up on the left side (and removed and moved some mangrove). Once I find something better, I'll remove the gravel and replace. Darker gravel makes colours stand out better, doesn't it?

Before:

After:

 

[mgamer20o0]

most plant substrate sold here in the states really dont have any real ferts in them. most of hte ones here have the ability to suck up whats in the water and have it for the roots if the water column runs out. doesnt hurt to add some but most say at least 50-50 mix.