cbwmn

Good morning all

I have a 16 gallon tall moderately planted aquarium (10 g footprint)
that has been up and running for 2 years now.
About 3 or 4 times a year it develops milky water (bacterial bloom) that is whitish and not green. The livestock is 8 neon’s and 1 SAE.
I don’t overfeed and push 2 ½ WPG with occasional 5 WPG burst for about an hour.
It has DIY CO2 injected through a HOB.
Out of four tanks, this is the only one with this problem.
In fact my 46G heavily planted is temporarily overstocked with 6 DD black super veil tails and 2 LF ABN’s.
I fertilize PMDD, FE, Flourish EI method w/50% PWC’s once a week.
On the 46 BF I do 3 X 30% PWC’s per week to accommodate the DD blacks.
My question is what causes this bacterial bloom in only that tank?
I am at my wits end on this one.

Thank you
Charles