For curly stick with the lv3 bubbler, you can't exit the room without it. Repeatedly tap the fire button to fire in a concentrated line (referred to as single shot from here on out) else she will overwealm you. Never save in the sand zone without a lv3 bubbler.
Balfrog? Charge and fire. Use single shot for the frogs.
For Balrog 4 you cannot take out the missiles. You need to practice dodging them. To get plenty of room to maneuver there is a specific point in time before he jumps where he will jump in the direction you were rather than are. So if you run and jump over him just before he does he will jump in the opposite direction givving you the full length of the room to dodge the missiles.
For Misery running along while charging the lv3 bubbler creates a vertical column of bubbles. Use this to your advantage.
For Ironhead more dodging is in order. Rest the bubbler as a pass comes in and towards the end of the inwards pass thin out the herd a bit, do not attempt to take on ironhead during the inwards pass. The outwards pass requires that you shoot ironhead at reasonably close range while getting out of the way if he moves too fast, dodging blocks and making a hole for yourself through the fish. Use the offshoots from your bubble shield to attack ironhead and defend yourself agaist stray fish and finish it off by releasing your stored bubbles. This takes practice. As with all of these fights never rush to take the final blow, be patient. If you can't hit ironhead then don't. Focus on survival. The thing that will kill you most of the time are blocks so forus on those first.
For the core fight draw him towards you so that you can stand right on top of him (you can pass through the core btw) and point blank him in the face. Standing within a pass through-able enemy and shooting ensures that all bubbles hit their mark. Remember this for Monster X as well.
For undead core focus on sue and use misery as a way to replenish health and exp. Misery won't usually attack unless you attack her. Then use your bubble shield for misery's spawning enemies until she is down and take on the core at your leisure.
