Aqua Jet Effect

Is the effect applied for a single turn or does it last while the monster is face-up on the field?
People told me it is until end phase, others said otherwise. I've been wondering since there are cards that have similar effects, such as "Wattcube", that have their atk raise effects last as long as the monster is face-up.

since the card only says
"Select 1 face-up Fish-Type, Sea Serpent-Type, or Aqua-Type monster you control. It gains 1000 ATK."
im gunna go with it lasts forever

The card would say "until the end phase of this turn" if it went away. The boost is basically permanent, unless reverted by another card effect.

If it would state "until the end phase then" only then.
I believe you ask this because sirocco doesn't states until the end phase, but it still until the end phase.
I have no idea what it is like that.