Guppies are peaceful little fish. Happy with their lot in a well planted, and well run aquarium to live in. The worst they can be is when males outnumber females and will pick or nip at tails of the other males. Giving them plenty of females usually sorts that problem in the tank. Guppies are easy to feed and will eat anything that has fish food written on it! Their guts are not massive so they only eat small amounts at a time. They will clean up the food with in minutes and will start searching for more if they see you around their tank. Where there are people, there is food in their book! You will see them picking at the plants usually algae but they do nibble at new shoots if they want.
Variety is the spice of life for every living thing and fish are not any different. Guppies go for most fish foods. The one mine favor is tubifex worms; buy these as small cubes of the dried worms. The cube can be attached to the glass in the tank and the free for all that follows is very funny and lasts until the frenetic feeding pulls the now sodden cube off the glass and floats away to be eaten more slowly. There are of course, the regular dried foods that you buy from any pet shop or supermarket. Look for the finer blend as do not forget they are small fish with small mouths. I also consider any fry that are there and that you are unaware of, will also like food that fits in their mouths. If we have peas for a meal, I usually throw two or three in the tank for the fish. The guppies are particularly partial to a few peas now and again. I would not over do it, but it is also a backup if you find yourself with out any fish food in the house!
There is the choice of “sea monkeys” or brine shrimps, you can buy these in a dried form and grow the amounts you require. Brine shrimps can be grown especially for guppies who adore them. The shrimp are particularly good for feeding fry, their growth rates improve accordingly. The shrimp are just another change in diet for your fish. Guppies love to be spoiled, but you must never over feed them as tempting as it can be. The last thing you want is decaying food on the bottom of the tank to cause diseases and water that smells.