Gourami With Cloudy Eye

I noticed this morning that my honey gourami has a grey patch on one of its eyes (photo attached). Is this something I need to be concerned about? If so, which medicines can I use safety with a gourami and scaleless fish?

Here is a bit of background:

I purchased the gourami 3 weeks ago and it seemed healthy. The aquarium was newly set up 7 weeks ago (after a house move during which my other aquarium broke). It was cycled straightaway (I used the existing gravel and filter) and there have been no rises in ammonia and nitrite at all (I was testing daily with an API Master Test Kit for the first few weeks, and continue to test at least weekly). The nitrates are between 10 and 20, and the pH around 7.5.

The only issue I have had with the new aquarium is hair algae. I strongly suspect that lighting was the cause as the lights were originally left on 10.5 hours, I lowered it to 8 hours and now 6 hours to try and resolve this issue. I am now dosing the tank with Interpet anti hair algae (I know this can be considered controversial but it's getting out of control). Looking at photos on my phone (I take alot of photos of my fish  the gourami appeared to have the patch on it's eye a few days prior to adding this, and anti hair algae doesn't appear to have affected the water quality or pH at all, and the fish are showing no signs of stress.

I can't see any obvious issues with other fish in my aquarium, or any other symptoms of disease. If I look really closely at the neon tetras I think I can see a tiny speck in the centre of their eyes, but not sure if I am imagining this or its how their eyes normally look as I don't spend alot of time looking at fish eyes!

Thanks!

I did a pH test this morning with an API pH Test Kit which expires in 10/2024. The reading was around 7.6.

I can't see any obvious signs of irritation and the gourami (and the rest of the fish) are behaving normally.

My gourami does sometimes eat algae from a small external sponge on the UV filter, which is quite coarse, so it is possible that he might have scraped his eye on that.

I will see if it improves over the next few days.