Just wanted to jump in a little bit here even though I am sure JM is much more of an expert than I am but I just had to say that the loaches are going to do much better in a larger group of three to five otherwise they can get stressed out and become highly reclusive. I agree with the idea that too many bottom dwellers is a bad idea, but dont count out clown loaches because they may get very large, up to and over a foot I believe, but they are such slow growing fish that many people can keep them for years before having to put them in a larger tank. Again, the group principle would apply to them as well.
What type of snails are you thinking about getting? I am not 100% sure, but I think the loaches are going to prefer eating actual baby snails rather than snail eggs. It is also pretty important to get snails, if you want to keep them, that are of a decent size so the loaches are more apt to let them live. If they are not getting enough food though, I wouldn't count on them not going after any snail, even the dojo loaches I believe. (only have real expeience with the clowns so far).
It really sounds as though you are already planning on having a big algea problem by the looks of your list with the two plecos and your mentioning snails, which are also going to eat algea. I just want to say that I have a bristlenose pleco as my only algea control in a 55 gallon and I have to suppliment it constantly because the tank just doesnt grow that much algea. Two other points would be that algea problems can be more easily controlled by keeping nitrates and other nutrients out of the water via water changes and not over feeding, among others, and plecos are not the best algea eaters available and become less and less apt to eat algea as they get older. Many of the smaller plecos also like or need some sort of wood to munch on from time to time and are pretty nocturnal and reclusive usually. If you just like the looks of the pleco, then more power to you, but they just arent the best 'tool' as far as wanting a fish as a clean up or workhorse in a tank. Dont get me wrong, I have a BN pleco in my tank because I really love these fish and if you are the same way, you should look into a more rare type like a clown pleco, which is nice looking and stays small (the smallest type I think, or close to it) or maybe a golden nugget or tiger pleco. here is a good link to have a look at what some other options could be:
http://www.liveaquaria.com/product/scateg.cfm?pCatId=837
Of course, some are more expensive than others, but this site will give you an idea of the costs you may see at an LFS. I figure that if this is the 125 gallon tank you are talking about, why not go all out!
JM brings up the good point about feeding blood worms and other meaty frozen foods in general. They are not always needed regularly unless the fish in the tank lean towards being carnivores. I would feed maybe one to two times a week with these and skip the flake food all together on those days.
You also do not need to feed your tank twice a day as far as I know with the fish on your list. I feed once a day and at the same time usually so that the fish are sort of expecting it and I avoid over feeding. I am assuming that you are talking about stocking the 125 gallon tank right? If so, keep in mind that while you have more wiggle room to make mistakes as far as the time it takes for a problem to occur with water quality issues slowly, but you still dont want to get too overboard since it takes equally as long to fix the problem in larger tanks. All the same rules should apply as if it was a 10 gallon tank and if you act accordingly, the tank is going to take care of itself more or less and algea wont be an issue at all.
