Glad you found the article useful, only too happy to be of service.
Would tropica plant substrate be a better choice than plain compost?
I’ve never used tropica substrate so I can't personally vouch for its suitability, especially for use in a lower energy setup. But from what I've read, it’s probably better suited to regular water column fert dosing.
However, being a cynic by nature, I can’t help thinking that it’s just another sanitized marketing ploy to exploit the ideological barrier that stands between many aquarists and the use of proper soil; but that's just between you and me.
I wish I’d thought of repackaging dirt in small bags and selling it at a premium, its not often you get to capitalize on a new set of cloths for the emperor.
I think it works out as being around 30 to 40 times more expensive than garden compost.
Rant over…I doubt it would prove to be any better than proper soil with its higher organic matter content and the benefits that infers on water chemistry and CO2 generation etc. And I doubt very much that in a lower energy tank without regular fert dosing it will have anywhere near the longevity, as a nutrient rich planting substrate, that proper soils have. So no I wouldn’t use it; I would spend the money on something else.
Finally, lighting. 9w seems very low for a 45 cm (approx 50 litre) tank. I was wondering about a 14w t8 tube instead. Is this a good idea? Should I run both? Thanks.
50 litres works out at about 11 imperial gallons so a 14 watt T8 gives you approx 1.3 watts per gallon; less if you’re an American. I use a 24 watt HO T5 full spectrum bulb in my 55 litre tank, which is just over 12 imp gallons, this gives me about 2.0 watts per gallon of fairly intense lighting, which is on for 10 hours a day with a two hour siesta period in the middle.
However, I am still experimenting with my lighting. I did have double that tanning my fish for the best part of 2 months without much in the way of algae, but upon close observation several species of algae had started to creep in from the edges, hence the lighting reduction. So now I’m keeping a watchful eye out and intend to vary the photoperiod if need be, but so far so good.
In a lower energy tank like mine, without regular fert dosing and CO2 injection, the only parameter I have control over is the lighting so it is important to get it right, but its not an exact science since so much depends on factors unique to each individual setup. But the beauty of a lower energy system is that there is greater margin for error, since, amongst other reasons, everything happens at a slightly more sedate pace.
I would stick with the T8 lighting and then add the other bulb later if and when it is needed, you could also vary the photoperiod of both together or separately; using timers makes this a no brainer.
Hope this helps Troi