Pearls. Throw them as you will, because some of us are swine on our bad days.
The Axelrod book has its merits, largely because he didn't write all his own stuff. He liked to use European writers, and I mean use. There was a tradition there that the knowledge and the sharing of knowledge came first, ahead of the money. So he would butter up the European scientists and researchers, offer them a forum for spreading their knowledge through his huge publishing empire (huge in the hobby) and then make a killing. He used to brag about it.
I used to work for TFH, as a paid by the article writer, just post Axelrod when they were trying to set a new course (which they have - I have great respect for them now) but were still stuck in the old ways. We discussed a book and they offered me about 10 percent of what other publishers later felt was a low basic advance. He ran a successful business, but created a lot of enemies with his cut throat approach. Plus, he was a braggart. Nowadays, many of the things he did would be socially acceptable, especially the self promotion. He was ahead of his time, and he made himself a millionaire.
I was very disappointed by all this when I learned it. That book was something I saved up for for a long time., as a kid. I got one of the TFH Innes versions first, and loved it. Innes could write, and the book had a warmth that shone through. I still look at Innes and enjoy it, as while it is dated, it offers some good hacks from the low tech era. I haven't opened the Axelrod brick in many years, but I still regularly look into the way larger Baensch series. I recently looked up info on a fish the internet sources had suggested had not been bred in captivity, and there in Baensch was a report of how it had been done 50 years ago.
I was working on a project way back when and decided to trace some myths about gouramis that people kept repeating. They tended to lead back to Axelrod, because in that era, he was dealing in fish we didn't know. He had a tendency to make guesses as to how things would be, and he presented them as guesses. I have to give him credit there. But later, the 'may' and 'could' statements vanished, and the guesses became 'facts', often in the hands of other writers. So you have to read him with a grain of salt and double check with other sources. He was a modern guy in his greed and lack of dignity about it, and would have had a great youtube channel.