Very nice! Well-written and no spelling mistakes.
These are my notes.
-Mention the many rules of Dutch style and link to some guides
-Credit the photos
-find a better Iwagumi example
-In “Heater and thermometer” delete the Aquarium Coop Sentence
-In “CO2 (Optional)” delete reference to Wikipedia
-Also delete statement about Excel, or explain that it’s an algaecide and doesn’t appreciably boost CO2
-Also list and explain CO2 equipment and types of diffusers and reactors
-In “Water test kit” explain that test strips are very inaccurate, so liquid kits are preferred
-In “Fertilizers and Nutrients” include some info about mixing solutions from dry salts, dry dosing, and using rotala butterfly
-In “Rocks” explain how to test rocks, and I’m not sure it’s good to recommend boiling
-In “Planting” specify cyanoacrylate gel glue
-Also remove reference to Aquarium Coop and recommendation not to move plants around
-In “Start Equipment” link to or explain how to adjust CO2 to the correct level
In “Cycling and Observing” link or explain the fishless cycle
-In “Temperature and Chemistry” explain not to “chase pH” but rather to adjust and keep gH and kH stable, and that tank-raised fish are less likely to need the exact parameters of their species origin
-In “Start small and simple” Dutch is simple?
-In “Choose fish wisely” list a smaller fish than Pearl Gourami. Possibly also link to Aqua Advisor as an aid?
-In “Maintain Chemistry” remove Aquarium Coop reference
-In “Be patient and observe” change to “remove the affected leaves, but don’t throw away the plant…” for clarity
I hope they’re helpful and not just nitpicking.
