Beige see-through spots on plants (pics)

[Bethanyjxne]

Hello all! I hope you’re well!
I’m currently after some answers as I can’t find them anywhere, I’ve had my planted tropical aquarium roughly 4 months, and yesterday I noticed what appeared to be these see through beige spots on two of my live plants and my seachem ammonia checker which is on the inside of my tank. My tank is fairly small (54L), maintained at 25 degrees Celsius, and fully cycled, I’ve never had this issue before and I’ve tried to look for answers online and I’m still unsure! I was just wondering whether anyone could identify what it is from the pictures attached and let me know if I need to be worried, and how I can get rid of it if it is troublesome! Many thanks,
Beth
ps. Please be kind I’m new to the hobby x

 

[Colin_T]

Hi and welcome to the forum

Can't see anything because there is a big ammonia alert badge in the picture covering everything.

 

[Bethanyjxne]

Hi and welcome to the forum

Can't see anything because there is a big ammonia alert badge in the picture covering everything.

Hello! Thank you! The alert badge is there because it also has the same round spot on! You can see the plant in the background x

 

[itiwhetu]

A better picture please

 

[Deleted member 149562]

Those patches of beige look a bit like diatoms.....though diatoms don't usually go so well defined on the edges.

What is your maintenance routine (water changes, substrate hoovering etc)?
Are you using any additives apart from dechlorinator?
What is your lighting routine?
What are your most recent (ideally today) test results?
How long has the aquarium been up and running (including any cycle time)?