Is my current aquarium lighting suitable?
I'm relatively new to aquarium keeping, with a couple of years of practice, and would much appreciate some opinions with regards to my current lighting setup.
A few months ago I purchased a 54 litre/14 us gallon aquarium which came fitted with a CFL bulb listed as 11W E27 with a colour temperature of 6500k. I've never been particularly strong when it comes to the lighting aspect of aquarium keeping, so I was wondering if the experts would consider this adequate for my tank. I'm suspecting it's not, as some of my once red/purple plants have lost a lot of their colour.
The tank is planted and stocked with fish, and the water depth is approximately 30cm/12in. Due to the positioning of the bulb in the hood, the left half of the aquarium is bathed in light, whereas the right half is a little more shaded. A couple of the plants on the right are looking somewhat sad, so I'm wondering if the light is just too weak (water conditions are fine, and some acclimating shock was expected, as some of the plants are just a couple of weeks old in the tank).
My current plants are as follows:
A half dozen marimo, Christmas moss, Alternanthera reineckii roseafolia, Ceratopteris thalictroides, Lilaeopsis brasiliensis, Anubias barteri vars. nana and caladiifolia, Ludwigia repens 'Rubin', Echinodorus amazonicus, Crinum calmistratum, Cardamine lyrata, Microsorum pteropus, Hydrocotyle verticillata, Hornwort, Eleocharis parvula and Limnophila hippuridoides.
It's the latter two plants which are suffering on the right side, and I'm aware that the Limnophila has a higher light requirement than most of the rest. The Alternanthera reineckii is also having problems, even on the left side, but I've never had much success with that plant in the past anyway. The Ludwigia is growing well, but its normal ruby colours are only present where it touches the water surface, being green otherwise. For the record, the Hornwort is partially anchored and is not majorly obstructing light to any of the other plants.
So, that's my current setup. The fish are fine, but I wonder about the plants. Does that amount of light seem reasonable for the tank size and plants? If not, what would you suggest as an alternative. The hood and lighting is solidly fitted onto the tank, so I'm unsure how I'd alter it, honestly.
A huge thanks for reading my post, and for any input you can offer! I'll happily provide more info upon request if I'm able.