The following table provides suggested dilutions (sample volumes) based on estimated BOD result:

Est. BOD (mg/L)	Dilutions (ml)
600	1,2, 4
500	1,2,5
400	2,4,6
300	2,5,8
200	3,8,12
150	4,10,15
120	5,12,20
100	6,15,25
75	8,18,30
60	10,25,40
50	12,25,50
40	15,40,60
30	20,50, 100
20	30,60,100
10	60,120,200
6	100,200,300
4	200,250,300
2	300,300,300

* based on 300 mL in standard BOD bottle.

We have also seen that the middle dilution should be 1200/Est BOD:

If your estimated BOD is 90 mg/L,  1200/90 = 13.3, therefore run dilutions of 10,13,and 15 mL .