Advice Needed For New Tank

[suzanne]

I have just got a new tank !!
its an orca 20 gall cube type aquarium.
I plan to have a moss carpet, my redwood roots from AE, some java ferns, anubias and poss some pellia or riccia.
4 dwarf rainbows, a shoal of neons & 2 ottos.

I need advice on the following:

lighting, currently is 24w with reflector. most of the above plants tolerate low light so is this adequate ? I was possibly thinking of adding an extra wattage via some cold cathode lighting..

Co2 input, I will be using my DIY kit as this helps lower my pH as well as plant benefits but wonder about positioning of the diffuser. Filtration of the tank is all hidden at the back and there is a section with room to place a heater, can I put the diffuser in there ? I have a permanent co2/ph tester that would be visable.

Substrate - what is best to use if I am going to grow a moss carpet? none of the above plants would be rooted so it seems a waste to pay out for expensive soil. I plan to grow the moss on some wire mesh.

Filtration - the built in 3 stage filtration looks okay with loads of room for lots of media, but it takes in water from the top left of the tank and returns water from the top right. will this just circulate & clean water at the top? all the filters I have used before have had inlets at the bottom of the tank...

any other advice ?

thanks, Suz

 

[nry]

Can't comment on anything other than the CO2 diffuser placement: my suggestion is that this is trial and error. Providing you have a permanent test for CO2 it is easy enough to put the diffuser in, check levels after a good few hours. Move diffuser, re-check again in a good few hours.

I've been trying a few different positions in my tank and loads of stuff affects the efficiency including plants, decor (wood) and water flow around the diffuser. I have wondered about putting the diffuser inside the built-in filter in my Juwel tank but have not yet tried this.