I have followed this thread and feel I must correct some of the information. There is also a serious issue with the nitrite.
First, the algae. Soccermatt has a new tank which is still in the initial cycling. All such tanks experience fluctuating water conditions until the biological stability is reached post-cycle. "Cycled" as I'm using it means the biological state of the aquarium is basically stable and relative to the fish, plant, invertebrate and bacteria life in it at that time. Once this state is reached, it is easier to control algae because the biological stability will remain unless the aquarist does something or allows something to affect it negatively. This normally takes 2-3 months. As I use the term, it is more than just the initial cycle of ammonia/nitrite/nitrate.
In new tanks that have not yet cycled algae of various types frequently appears. A nitrite reading of 5 (which if accurate would kill any fish if there were any in the tank) clearly shows you are in the second stage of the cycle. I would suggest removing the algae from the glass and waiting things out. Algae is common in all aquaria that are balanced, but the balance keeps it in control. Your plants and light are fine to achieve this, provided nothing is done to negatively affect the process during and post-cycling.
Second, water changes. These can assist in algae control by maintaining stable water parameters. Once established, a tank with a moderate to heavy fish load must receive a weekly (at the least) partial water change, and it should be 50% or more. With fewer fish, and having plants, this can be lessened. But most of us like more fish in our tanks than a lax maintenance system can support healthily. A regular weekly pwc of 50-70% will not harm the fish, in fact they will thank you for it. I've written at length elsewhere on the issues with pollution and water changes.
During the cycling process, water changes do not hamper the cycling. Bacteria (nitrosomonas and nitrospira) colonize all hard surfaces under water. The substrate (gravel) should not be disturbed during cycling so as to encourage bacteria colonization; similarly the filter should not be rinsed or cleaned unless absolutely necessary to keep the water flow through the media--and this is normally not an issue at this stage when little life is in the tank.
Back to your nitrite reading; in a planted tank I would never expect to see nitrite readings even during cycling. Is the tank well planted? If it is, there should not even be a cycle at the beginning. I have set up dozens of new tanks with plants and fish added the first day and never had a cycle. I may have more comment when I know a bit more about the number and type of plants.
To the otos, these fish are extremely sensitive to water parameters and water quality and should never be added to a tank that is not biologically mature. Not only have countless other aquarists stated this, but I have experienced it first hand. When I set up a new tank, and if I intend to have otos (there are other equally suitable algae control fish that are interesting), I never add them until the tank is mature (2-3 months) and then only if the forms of algae they will eat are present. Without acceptable algae in the tank when they are introduced, otos frequently die within days. They will readily become accustomed to eating tablet/pellet foods along with the bottom catfish, but from my experience and others this does not occur at introduction. Without algae present when introduced they will almost certainly starve.
Second point on otos: they will only eat common green algae and diatoms (brown algae). I have never known, nor ever heard, of otos eating brush algae or hair algae. They may graze through it, but they will not eat it.