For any game out there, there's always some geek who just has to try out all the options and figure out what's the best strategy. That'd be me. I'm one of those. Since I've just restarted Aqua Pets, I'm working through the early levels (now at level 18) to see which combos are best.
Catching Fish -- some strategies
By the way, although there are rumors of "cheats" for the game, the pages I get directed to seem to be full of ads. There's no list of hints or cheats for Aqua Pets running around in the wild. On the other hand, it's a pretty straight-forward game for the Android, based on a random calculator -- it can be difficult to beat random number generators.
The new "luck meter" and pole/bait combos have caused a bit of confusion, particularly since some of the baits are VERY expensive (4 pearls, for instance, for rainbow pellets.) Pearls are hard to come by unless you buy them directly from Bionic Panda or start sharing your tank. I did buy a packet of glowing blue pellets and tested it out. The catch rate of rare/legendary/uncommon fish was high -- about 70%. However, unless those fishes in my tank start dropping pearls, I don't foresee a lot of buying bait with pearls.
Currently, I have one legendary fish (the Loose Triggerfish), which was NOT caught on the expensive bait and 19 rare fish (I caught more than that, but I've sold duplicates.)
At level 17, I found that fishing with the purple rod and spotted worm resulted in a catch rate of over 50% purples (rare fish.) With the orange worm, I caught only one purple (rare), and 3 uncommons.
Catch rates of rare/uncommon fish on black bug bait are around 5%-15% for any type of rod you use (some types of fish are caught only with a certain rod -- but you can expect a lot of common fish along with the special fish. Other bugs/worms give a higher percentage -- when you're a low level (under level 10), the orange and green bugs give about a 30-40% drop rate of rares and uncommons, but this drops off as you hit a higher level. Aqua Pets recommends using the spotted worms and orange worms (after you hit level 10) and I am seeing about a 35%-45% average catch of rare/uncommon fish with that bait.
Since it's based on luck (a programmed randomness factor), I have had times when I bought orange worms and only caught common fish.
The Aqua Pets Facebook team is watching feedback and there's some indication that they'll change the luck percentages.
Some notes on rods -- a lot of the food fish (Peach Fish, for example) can be caught with the wooden spoon -- however, I did manage to catch an Apple Fish at level 10, so this isn't a hard and fast rule. You can catch mechanical pets using a metal antennae and the bone rod, of course, is for prehistoric critters.
The current consensus in the Facebook group is that the "luck boost" doesn't do much at all. In other words, when you capture ten in a row, you get a "luck boost" -- however, people are often seeing only common fish caught on that "lucky cast." My strategy is to use up black bugs until I'm within 2 casts of the luck bonus, then make the next six casts with expensive bait.