About 40% of potions in my game have a value of 0, I am quite confused as to what could be causing it.

http://i.imgur.com/Bnhvt.jpg

Masters for jam50000.ess:001  Morrowind.esm002  Tribunal.esm003  Bloodmoon.esm004  GOTYFullTidyZeroMPPv2.01.esm005  Texture Fix - Bloodmoon 1.1.esm006  Morrowind Patch 1.6.5 Beta (BTB Edit).esm007  Texture Fix 2.0.esm008  GDR_MasterFile.esm009  Morrowind Advanced.esm010  MW_Children_1_0.esm011  Poorly Placed Object Fix  1.2.esm012  Ward of Akavir.esm013  MRM.esm014  TR_Data.esm015  TR_Mainland.esm  (Version 1.1)016  MCA.esm017  GOTYSTMPPPatchv1.0.esp  (Version 1.0)018  SirLuthor-Tools.esp019  Unique Banners and Signs.esp020  Windows Glow.esp021  Haldenshore_1.2.esp022  Key Replacer Trib & BM.esp023  Dagger of Symmachus.esp024  abotWindowsGlow.esp  (Version 1.1)025  PSsorticon.esp026  Statue Replacer - Normal.esp027  MW_Adv_Required.esp028  bones.esp029  Shieldfx.esp030  OR_Fang.esp031  OR_ForkH.esp032  Book Jackets - Morrowind.esp033  Book Jackets - Tribunal.esp034  Book Jackets - Bloodmoon.esp035  Barabus' fireplaces 2.esp036  Better Clothes_v1.1.esp037  NewBlood_MwTbBm1.1.esp038  Neo's Unique Creatures.esp039  BetterClothesForTB.esp040  correctUV Ore Replacer 1.0.esp041  KS_Julan_Ashlander Companion_1.3.esp  (Version 1.3)042  almalexia armor.esp043  Windows Glow - Tribunal Eng.esp044  Windows Glow - Bloodmoon Eng.esp045  UAR_EbonySarano_v2.esp046  Better Solsthiem Creatures.esp047  Thirsk Expanded Family.esp048  Windows Glow - Raven Rock Eng.esp049  WA_Signy_Signposts(!).ESP050  New Veloth's Judgement 2.esp051  Better Skulls.ESP052  Particle Arrow Replacer.esp053  JAC_Jasmine.esp054  UAR_Bloodworm_v2.esp055  Bloated Caves.esp056  UAR_ChodalaBoots.esp057  LGNPC_PaxRedoran_v1_20_GOTYST.esp  (Version 1.20)058  Graphic Herbalism.esp059  Graphic Herbalism Extra.esp060  LGNPC_NoLore_v0_83.esp  (Version 0.83)061  LGNPC_GnaarMok_v1_20.esp  (Version 1.20)062  LGNPC_AldVelothi_v1_20.esp  (Version 1.20)063  LGNPC_MaarGan_v1_20.esp  (Version 1.20)064  LGNPC_HlaOad_v1_32.esp  (Version 1.32)065  LGNPC_Aldruhn_v1_20.esp  (Version 1.20)066  LGNPC_Aldruhn_v1_22_suppl.esp067  LGNPC_Pelagiad_v1_31.esp  (Version 1.31)068  LGNPC_TelMora_v1_30.esp  (Version 1.30)069  LGNPC_Khuul_v2_21.esp  (Version 2.21)070  Westly's Master Headpack X.esp071  Illuminated Order v1.0 MRM.esp072  BT_Whitewolf_2_0.esp073  SNR_ThievesStep_Standart.esp074  The Neverhalls.esp075  MA_snowprincetomb_v3.esp076  Psy_IronMeshImprove_Uniques_BME.esp077  AtmosphericSoundEffects-3.0-Tribunal.esp078  More Better Clothes.ESP079  GCD v1.08 with Startscript, fixed [Galsiah].esp080  Golden Gold.esp081  guarskin_drum_replacer.esp082  UniqueFinery.esp083  Unique Jewelry and Accessories.esp084  Fliggerty's Fleeing Fetchers.esp085  OTR_Coast_Variety.esp086  Clean MCFC_1.0.esp087  imperial chain fix.esp088  Murderous Dreams_Safe.esp089  ExcellentMagicSounds.esp090  Morrowind Crafting 2-1.esp091  ImprovedTeleportation2.0.esp092  GH MC Patch.esp093  UF_HortRobeF001.esp094  MQE_MainQuestEnhancers.ESP095  Creatures.esp096  BTB - Alchemy.esp097  BTB - Character.esp098  MCA - Guards Patch.ESP099  BTB - Equipment.esp100  BTB - Spells.esp101  Morrowind Crafting Equipment.esp102  BTB - Settings.esp103  DreadKnight.ESP104  frostmoth_repaired_v0_31.esp105  Books of Vvardenfell.esp106  Less_Generic_Nerevarine.esp  (Version 1.21)107  Less_Generic_Tribunal.esp108  LGNPC_VivecFQ_v2_20.esp  (Version 2.20)109  Vurt's Grazelands Trees.esp110  LGNPC_TelUvirith_v1_20.esp  (Version 1.20)111  LGNPC_SecretMasters_v1_30.esp  (Version 1.30)112  sm_ForgottenHalls.esp113  LGNPC_IndarysManor_v1_51.esp  (Version 1.51)114  Animated Morrowind.esp115  New Voices.esp116  Less_Generic_Bloodmoon.esp  (Version 1.2)117  Sleepers, Awake!.esp  (Version 1.1)118  Illuminated Order v1.0 - Bloodmoon Compatibility Extras.esp119  Clean jac_bearcub.ESP120  LeftGloves_Addon_v2.esp121  Welcome to the Arena! v5.5.esp122  TravelingMerchants_v2_3.esp123  abotGuars.esp  (Version 1.17)124  True_Lights_And_Darkness_1.0-NoDaylight.esp125  abotSiltStridersTR.esp126  Quick Char.esp  (Version 1.2)127  Firstguard_Armour.esp128  horationpcenhanced12-bm.esp129  Better_Sounds.esp130  Vurt's BC Tree Replacer II.esp131  abotBoatsTR.esp132  npce_mwse_patch.esp133  abotRiverStridersTR.esp134  New Bodies - Mature.esp135  Service Requirements (BTB Edit).esp136  Necessities for Purists 2x.esp137  WolfCompwhite_ver3_0.esp138  Healing.esp139  Carry your Bedroll.esp140  NfP addon.esp141  DN-GDR BTB MRM.esp142  MCA - TR Addon.ESP143  Piratelords Trade Enhancements.esp144  PTE - BC Patch.esp145  Mashed Lists.esp

Its a feature of BTB to avoid giving you infinity gold from alchemy.

Of it you mean non self-made potions I have no idea.

a lot of economy mods also set potion making to zero too. not sure if piratelord's does or not.

If it is non self-made potions ... I see that PTE is loading late, and it sets autocalc on for many potions, which may interact with the GMST change BTB - Settings makes to the iAlchemyMod GMST.

Just a possibility, but I have not tested it.