it will help you in the short term. But after 2-3 generations, the tyranids will evolve immunity and your poison will not affect them. Your best bet is to use it all at once to kill as many as possible, just to create a window of opportunity to escape from the planet and then enjoy the upcoming exterminatus.
Honestly people truly lack the understanding or fear a Tyranid hive fleet even one as small as a splinter fleet is capable of, where the only effective means of preventing their expansion and the most capable of dealing with the tyranids would be Star Wars CIS, where due to using droids, means that very little in the ways of biomass is actually being consumed, all the while droids can be recovered and recycled, that being said that f a single hive fleet makes it to say a world like curascant or especially kashyk then the Star Wars universe has a threat unseab before even rivaling that of the yuzan vong invasion, since tyranids are more or less resistant to plasma based weapons such as in the case of the tau, in which due to their highly thick carapaces, made them virtually invulnerable to thermal or plasma based and even low to mid level ballistic weapons such as the bolter or auto cannon would have difficulty, and considering that the tau are more technologically advanced than most other sci fi universes, only to get absolutely brutalized by a mere splinter fleet, says a lot about how dangerous the tyranids truly are, and again outside of trans dimensional beings like say the ancients from stargate or more mechanical creatures like the replicators might pose an issue due to the lack of having organic parts, reducing their ability to absorb new biomass, the Zerg on the other hand or even the borg would prove to be more idealistic targets since the Zerg are all biological and even the borg are somewhat organic in nature even if the mechanical components are ((less digestible)), that being said most other sci fi or even fantasy universes makes use of the warp, in which case they’re im effective against magical based attacks in which its close to impossible to counteract without warp powers to boot.
