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Formalin Treatment for Trout Eggs

milliliters (fluid ounces)

Seconds to Concentration
Fill 1 gal GPM 2000 ppm 1667 ppm 1429 ppm
Container Flow 1:500 1:600 1:700

4 15.0 1703(58) 1420(48) 1217(41)
5 12.0 1362(46) 1136(38) 973(33)
6 10.0 1136(38) 946(32) 811(27)
7 8.57 973(33) 811(27) 695(24)
8 7.50 852(29) 710(24) 608(21)
9 6.67 757(26) 631(21) 541(18)
10 6.00 681(23) 568(19) 487(16)
11 5.45 619(21) 516(18) 442(15)
12 5.00 568(19) 473(16) 406(14)
13 4.61 523(18) 436(15) 374(13)
14 4.29 487(16) 406(14) 348(12)
15 4.00 454(15) 379(13) 324(11)
16 3.75 426(14) 355(12) 304(10)
17 3.53 401(14) 334(11) 286(10)
18 3.33 378(13) 315(11) 270/(9)
19 3.16 359(12) 299(10) 256/(9)
20 3.00 341(12) 284(10) 243/(8)

* to calculate formalin treatment in milliliters = (gpm)(ppm)/17.61
gpm = gallons per minute
ppm = desired parts per million of formalin

* 15 minute treatment time – Use an appropriate
dispenser
* DO NOT treat eggs that are
hatching

Written By

Photo of Skip ThompsonSkip ThompsonArea Specialized Agent - Aquaculture Serves 13 CountiesBased out of Haywood(828) 456-3575 Skip_Thompson@ncsu.eduHaywood County, North Carolina
Page Last Updated: 5 years ago
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