1” per gallon has been around since we only had angle iron tanks and most people only had undergravel filters then, we have moved on a lot since I was a boy
Just compare what the turnover is now on most aquascapes (x5 is usually minimum accepted these days I personally go x10 with filters not wave makers) not to mention how much plant matter there is to strip nutrients out of the water column
Hands up who adds Ferts regularly because the fish don’t provide enough
When I say 25mm per litre that’s for small slender fish not deep bodied fish like Discus or Oscars etc
You have to work out roughly how many neons = 1 fully grown discus
Please remember We’re talking about advice for an accomplished aquarist not a newbie
If you ever get the chance to visit a fish keeper who has his own fish house and breeds fish then do it
Their fish grow quickly, are strong and healthy and are packed in to the tanks especially the young fish, probably uses air driven sponge filters or their own diy filters, feed lots of live foods as much as they can
They will do a 50% WC each week
At the end of the day it’s a personal choice if the tank has large areas of no fish and the owner wants to add a few to fill that space then they can
I’m only saying that in my opinion 225mm of fish could be added safely
That’s only 7 fully grown neon tetra size fish (giving them 30mm at adult size)
You also have to take the foot print of the tank into consideration, it’s a standard cube not a tall narrow tank
I expected aquascapers to be on the light side or even under stocking their tanks as the fish generally are not the reason for having an aquascape they are more of an accessory
Where I’m the opposite Fish first, decorations 2nd. Even if I want to breed something which would require a specific layout then it’s suitable decorated to suit the fish
www.practicalfishkeeping.co.uk
