首先，通过将饲料装入奶瓶并加入适量的水，充分摇晃后静置片刻，再让手把握奶瓶，让奶嘴浸没水下，直接让鱼儿前来吮吸这种喂鱼方法，不仅能够最大限度地防止饲料落入水中造成污染，还能有效防止饲料被过滤器和增氧泵吹散流失，从而减少了饲料浪费。

此外，这种喂食方法还极为方便地控制投饲量，只要感觉到鱼宝贝吃得差不多了，就可以立即拿起奶瓶。它还允许有目的照顾弱小鱼只，可以先将奶瓶放在水中，让抢食能力较强的吃食，将其喂饱，然后将奶瓶移到一个角落，为抢食能力弱的小鱼提供一个“小灶”。

更重要的是，这种方法可以加强与主人之间的情感交流，让fish feel closer to their owner, making them seem more intelligent and cute. It can also provide a fun way for people to interact with fish in public places like parks or hotels.

As for the types of food that can be used with this "bottle-feeding" method, any food that can be easily sucked through the nipple is suitable. This includes both natural foods such as brine shrimp, bloodworms, and spirulina, as well as commercial pellets or flakes.

It's worth noting that this method is best suited for larger fish species like koi or goldfish that are not afraid of humans and have a wide enough mouth to suck from a bottle. However, it does require some time for the fish to become accustomed to the feeding method. Plastic bottles are generally better than glass ones because they are lighter and easier to handle underwater.

In summary, using 20 yuan or less pet bottles to feed your aquatic friends offers several benefits: it prevents water pollution by minimizing food waste; reduces energy consumption by avoiding over-filtering; allows for easy control over feeding amounts; provides targeted care for small or weak fish; strengthens emotional bonds between owners and pets; and offers an engaging experience at public aquariums.