Confused about substrate mixing

I'm setting up a new tank. I want there to be a deep substrate so that this tank has some longevity for my plants. Sooo, I have 4 bags of unopened substrate as left overs from other builds, these are 2 bags of ADA Africana Normal 9L and 2 bags of UP-aqua sand 5kg. They are both plant substrates (i.e. enriched, but to different degrees and they are different sizes). Together and/or seperatly this is not enough to cover my 4ft tank. I'm trying to keep this build cost effective so I went to my lfs and asked if I can mix normal aquarium sand to bulk out my existing substrate. Lfs person said (a) Yes, I can mix my two plant substrates together and (b) yes I can mix sand into the 2 substrate mix to bulk it out. Aesthetically this would not be great and voiced this to him and he said I could scrape the mix into the center of the tank, and cap it with aquarium gravel filling in the border so from the outside you can only see gravel.

Hopefully that all made sense.

I haven't started the build but did buy 5 bags of sand to mix into the substrate. I also have lots of gravel left over from other tanks which I can rinse and use to cap. "Onto a winner" I thought.

I did some research to see if I should mix my substrate or simply layer it on top of one another. I.e. sand on bottom, then Africana normal substrate (nearly no enrichment), then up-aqua substrate (most enriched) with gravel cap on top of this.

There is so much information saying not to mix substrate types for various reasons so now I am confused. Is it mainly because of aesthetics or because it is somehow does something bad for the health of the aquarium?

I was only thinking of mixing the plant substrate in to add nutrients for the plants. I don't mind not using it but I'm just really confused and want to know if it is okay to mix substrate, okay/not okay to layer or just stick to one type? I've seen people cap their substrate with gravel before?

Can anyone please clarify for me? Thanks in advance.

 

I'm fairly certain it's just because of aesthetics. I've seen and heard of countless people doing basically what you have planned. I can't really think of a reason why it would be a bad idea to be honest.

 

I'm fairly certain it's just because of aesthetics. I've seen and heard of countless people doing basically what you have planned. I can't really think of a reason why it would be a bad idea to be honest.

That is what I thought as well! But wanted to double check. I actually have not used sand in my tanks, but read it is awesome for plants to root. What are your thoughts - if any - on mixing vs layering? (Sorry, I just want to get this right the first time!)

 

I haven't researched too deeply into the differences between the two so do take this with a grain of salt but I think if it were me I would do a bit of both. I would mix them so that there were still layers but more blended. Like sand, sand/africana, africana, africana/up-aqua, up-aqua, up-aqua/gravel, gravel. Having everything mixed together would make me worry about spots where it wasn't fully blended resulting in less than ideal growth. Layers would be easiest to set up but I would worry about growth being affected when the roots reach the next layer (not that that would happen, I'm just paranoid).

 

For aesthetics layer the plain sand on top of the enriched - roots will find their way down and it may help keep the nutrients in the substrate. You can top up later with root tabs if necessary.