NLS is by far the best IME. Are there other foods out there a lot better than Wardley and Tetra? Yes. Does that mean there is no difference between them and NLS? Not IME.
The problem is that so many foods are good enough to give great short term and even medium term results. Hikari, Omega One, Xtreme can all give great colors, growth, etc., but it doesn't mean they are equal. What we are looking for now is the best long term food for our fish, and this is what is extremely hard to determine and why there is so much debate about exactly which food is best. People tend to find something that works well for their fish (good colors, growth, health, and even breeding) and then stick with it, regardless of what else comes out. I don't think any of us go out and switch our fish to the newest food on the market to see how they do, as we shouldn't. But there are some issues we can go by to help us choose the best long term food.
Xtreme is not made by NLS. The only flour products in NLS are the minimal to allow it to stay together (so you have a pellet and not powered by the time you get it).
Similar sounding ingredients are not equal. For example 'fish meal' can mean many different things. In one company it is the scraps left over after the fish is processed for human consumption, so it can literally be the bones and internal organs off the floor in the factory. In another company's food it is the whole animal. I personally will not use foods with artificial colors (sorry Omega One, Ocean Nutrition, and most other foods out there).
With most companies if you compare their different formulas (herbivore, carnivore, spirulina, etc.) there is almost no difference in the nutritional percentages or the ingredients lists (or minimal like spirulina being a little higher in the list) yet the food is a completely different color. This is just the artificial colors because they know you want spirulina and herbivore foods to be green and carnivore foods to be red/orange/brown.
Higher fat content can lead to fatty deposits throughout the body that can cause a no symptom premature death. Fat levels over 10% are almost guaranteed to cause this. IMO effectively none of our fish die of old age, it is always long term nutritional problems and/or water quality.
I do not like 'natural' diets. For one they are not natural just because it is a whole animal food. Second is it requires the aquarist to be an amateur animal nutritionist, which always ends up being guesswork. Third is that most of the foods used to make a 'natural' food (frozen and fresh foods) are mostly just protein sources, equivalent to the first few ingredients in a high quality pellet. This will inevitably lead to incomplete and unbalanced nutrition, not ideal for long term health. Let the companies who know what they are doing provide a complete and balanced diet.
IME NLS has shown to be the best option in almost every situation. In addition, people who have actually tried it (exclusively for months, not for a couple weeks or mixed in with other foods) find it to also be surprisingly better than what they used to feed. All I can say is that you should try it. Get it locally if you can, or get it online if you need to, but try it. Truly try it exclusively for a few months and see if you can't tell the difference. I recommend the Thera+A formula because it has enough extra garlic to kill some parasites, and can help prevent health problems in general.
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. They are 17 days old and growing bigger and stronger every day.
. Every day they are doing something new.
