1: normally 2 layers is sufficient, base fert + substrate. But I tink some ppl jus use ADA soil la (mostly in smaller tanks, maybe tooeX if use on 3feet/more)
2: I dunno wat U mean by 3-4 times brighter, but theirs always wattage ratings on the tubes, so may wanna check it out. for my case, my 1feet use onli 11watt PL, cos its onli mosses. but normally 1feet 11watts - 18 watts shld be gd enuff.
3: for a small tank i'll jus use DIY CO2. can be home-made or get Nutrafin setup. need patience la, cos the rate can't really be adjusted, may cos algae prob.
(My advice la, maybe wrong.. go ahead n pt out anything, cheers)
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