For the BTD6 counterpart, see Bloontonium Reactor (BTD6).
For the building in BMC, see Bloontonium Generator.
Activate submerge using target option to detect camo, pop bloons, and reduce water tower cooldowns 15% (doesn't stack).
~ Description from BTD5 Mobile

Bloontonium Reactor (sometimes shortened to Reactor or Reactor Sub) is the fourth upgrade on path one for the Monkey Sub in BTD5. It allows the sub to reveal Camo Bloons, in the same way as Submerge and Support, but when submerged, it will also pop bloons within its radius. As a bonus, it reduces water tower ability cooldowns (First Strike Capability and Monkey Pirates) by 15% if they are within its radius. It should be noted that while the cooldown bonus does not stack with other Bloontonium Reactors, it will still stack with High Energy Beacon and Hotter Cooldown (85% total if hotter cooldown is fully upgraded, or 65% total on BTD5 Flash with the premium upgrade).

Strategies[edit | edit source]


Update History (Bloons TD Battles Mobile)[edit | edit source]


Nerf.png Bloontonium Reactor price increased ($2500 → $2800).


Buff.png Bloontonium Reactor now automatically switches the tower into submerged mode upon purchase.


Nerf.png Fixed a bug where Bloontonium Reactor's water tower cooldown decrease stacked with any other Reactor in range

Gallery[edit | edit source]

Trivia[edit | edit source]

  • In BTD5, this is one of the few upgrades that has infinite popping power.
    • In BTD6 it has been nerfed to only pop up to 70 bloons per pulse (or 30 before Version 2.0).
  • A submerged Bloontonium Reactor acts like a Ring of Fire, but it is used on water and it has Camo Bloon detection, as well as reducing the cooldown of nearby water towers.
  • In Bloons TD Battles, with a regular defense, it can stop a Rainbow Bloon rush.
  • In BTD5 Flash, multiple Bloontonium Reactors placed close to each other can stack their popping power, and 2 to 3 of them can stop even a full Regrow Ceramic if placed precisely.
    • In Mobile, Bloontonium Reactors popping power does not stack.
  • In BTD5-era games, although the description says that the cooldown reduction does not stack, it actually does stack with multiple subs, which can further decrease the ability cooldowns. Thus, using at least seven of these will fully cancel the ability cooldown, allowing for hypersonic abilities. In BMC Mobile, this exploit is incredibly useful for reaching high rounds in Contested Territory if the current map is set on Lake or River Terrain and First Strike Capability is used, allowing the player to take out even strong Z.O.M.G.s very quickly and easily. The same thing is true when fighting Bloonarius.
    • This was fixed in BTD Battles Mobile, preventing the ability cooldown reductions from stacking.
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