I do not agree with checking as many sites as possible. The odds are two things will happen. You will see incorrect information on many of them and you will not know which ones are good and which are not. So perhaps I can also suggest where not to look for good fish information.
Much as I hate to say it, this, or any other general fish sites, are mostly not good places to go for information. Even some specialty sites may not be as good as others as well. The reason for this is twofold. The fish we keep have two different levels if information. The fist deals with them in the wild. How they live, parameters, diet, other species in the same territory etc. This information is the basic facts about any fish. But then we put them into tanks and things are not the same. Space is smaller, parameters are different and so is diet and especially the other fish we add or do not add.
Keeping fish in captivity alters a lot about their lives compared to the wild. This can be amplified when fish are born and raised in captivity as well. Tank raised fish can do better in parameters their wild counterparts might not. As a result things can be different between the fish in the wild and in our tanks. However, certain features do not change just because a fish becomes a tank denizen. Dietary needs do not change, reproductive methods do not change- a mouth brooder doesn't become an egg scatterer etc. And to this extent it is important to be familiar with how a fish lives in the wild. And the experts on this need to have studied them there. This means almost no general fish site has members who have studied and collected the fish in the wild you are trying to research. Almost any narrative we see on a general fish site that deals with the fish in the wild is not based on first hand experience, it has been taken from what was written by somebody else. So who knows what has been "lost in transition" or who the somebody else is unless the information is foot noted.
I know if I go to PlanetCatfish and ask a question that there are a number of people who can answer based on their first hand experience in the wild. I also know there will be plenty of folks who will answer with information on the fish in captivity as there will be many people on the site who have kept them for many years and often spawned them as well.
This does not mean there is not good information on general fish sites, it just means that if you want the broadest information in terms of how many species may be profiled and the best and most reliable information, you need to do your homework. The trick is not simply to find information but to find accurate and useful information.
The three sites I suggested are the ones I have used for some time. They are not always in agreement in what they write, but they are usually pretty close. If after consulting them I am not sure, I will then turn to individuals whose input I have come to trust based on their credentials and experience.
Simply having kept a fish or done something in their tank once is not sufficient, imo, to make somebody qualified to be correct about what they say. I have watched this for going on 14 years. In January they are posting about how to cycle their first tank and in May they are advising others how to do it. They have a young fish for a few moths that is normally aggressive and they will post their fish seems to be getting along fine with the other in the tank and is not aggressive. The problem is a year later when this fish is eating its tank mates, that same poster doesn't revisit the thread and apologize for being mistaken. This information just sits for other newbies to see.
So if you want to rely on a member on a general site for good info, you need a good reason for believing they have the experience and knowledge needed. To be honest this is a lot harder to discover than the actual professionals are to find. You can look up Ingo Seidel, Paul Loisell or Pam Chin for example. Try that with the screen names on a general fish site.
What this boils down to is using the same standards that one should use when researching anything- know your source, especially when on the internet.
As always, the above is just one person's opinion.