Tripling tank size, fish suggestions?

Thanks discus! I would be interested in discus. Are they still hard to keep? I have read conflicting information. The idea of something so big gorgeous and peaceful seems perfect. Could you tell me the sites of some online sellers that you think are reliable? Can you mix colors, or would that constitute a different group in the tank?

Foremost, and contrary to popular belief, discus are not at all hard to keep, SO LONG AS you make sure you get good quality, healthy, well-shaped stock, of a reasonable size, from a reputable supplier in the first place.
That conflicting information you have heard/read, almost always comes from people who have not gotten their (properly-sized) discus from a good source, and have not followed a few simple rules for keeping them successfully. It's not difficult, and I would be more than happy to walk you through it carefully, should you ever decide to get started with discus.
Tell me where you are located, and I'll try to put you on to the best sources to get those quality fish, hopefully somewhere near you.
And of course, you can mix and match colors - whatever turns you on - makes no difference to the discus and how they get along !

What's their lowest comfortable temeprature?

I would say that 82 F is about the lowest temp that I would keep domestic, farm-raised discus in, to ensure they feel as comfortable as possible over the long term. Apart from that, wcs, maintaining good water quality & conditions, tank cleanliness, and proper diet, are all it takes to be successful. And that's not difficult, just takes a little extra effort and attention. No rocket science here.

After keeping fish for over 50 years, since I was a kid, and keeping discus, on & off, for many of those years,
there is nothing more pleasing to me than being able to help aquarists interested in discus, to get off on the right foot, be successful, and dispel those ugly rumors about discus being super-sensitive, delicate, and very difficult to keep. It's just not so !
Try it - it's the most satisfying part of this whole fish-keeping hobby - even marine/reef fish-keeping, which I have done several times too.
Pardon my rambling on, but I continue to read so many negative stories about keeping discus, that I feel I must do something to try & change some people's opinion or attitude about discus-keeping.
They're just a bit more expensive to acquire, that's about all - but very much worth it to keep the 'kings of the aquarium' - as beautiful as any salt-water fish you can have.
 
Then, your best bet would probably be Hans' Discus, in Baltimore, Maryland, I believe it is.
Google him, or get his website by checking out the sponsors' section on simplydiscus.com
Hans has been around a long time, and stocks very high quality 'Stendker' discus.
He is very accomodating, is extremely experienced and knowledgeable, has reasonable pricing and low shipping rates, and I know that he has had many thousands of very satisfied customers.
Check him out.
The next best source I know of, fairly near you for shipping purposes, would likely be Central Ohio Discus - Mike Beals, who sells good quality discus as well. Also a reputable sponsor on simplydiscus.com.

BTW, if you are seriously interested in discus, you may want first to have a read through my' Beginner's Guide to Getting Started with Discus', located here as a sticky in the Cichlids section, Angel Fish & Discus sub-section.
 
Thanks Paul. Are there any particular breeds you reccommend, or is it just what colors I like and they are all the same otherwise?
 
Not even half, if I understand what you mean.
In a 125 gal, you could readily keep up to a dozen adult-sized discus, along with a reasonable number of other smaller 'dither' fish - no problem.
e.g. 20-30 Cardinal Tetras, along with 8 to 10 Cories. Something like that - but there are many other combinations - tell me what you like, I'll give you some numbers, and whether or not they are compatible.

Answer your question ?
 
Well let's see I like glowfish, I have tetras, was thinking danios too, maybe flesh out the cherry barb school by a couple more, the betta. I was looking at blood red hi fin swordatails, but I wonder if the betta might confuse them for males. I'd like some non fish too but I can't find anything besides frogs that aren't dangerous. The Black Kuhli Loach seem like a safe alternative, looks like an eel :) I found the brazilian\amazon puffer fish is peaveful (no idea where to get them) Maybe the rainbow cichlid if it will be peaceful solo. I had blue gourami, but they were like watching paint dry. Basically I'd like some colorful schools, a few individual fish that I can actually differentiate (who knows which is which in a school), and something unconventional, like the quasi eel kuhli. I know there are tons out there, but I only get so many ideas looking around petco and such. Any ideas?
I checked those two sites, they seem nice. They don't have some I was interested in, http://www.liveaquaria.com/product/aquarium-fish-supplies.cfm?c=830+834 shows some nice ones, I'd love the Yellow Malboro, a deep red one, a blue, and that checkerboard is gorgeous! Would I be looking to get 5 or 6? Even if I can fit more, I don't like looking at those aquariums with big fish that seem crowded or relatively small to the big fish size
 
Choosing suitable tankmates for discus can be a bit tricky.
While a good number of fish are appropriate tankmates, the majority are not.

Most of the fish that are unsuitable, is simply because they can't tolerate the higher discus temps for very long, and soon begin dying off, one by one (e.g. Neons).

A good number of others are simply too active, moving around constantly and rapidly, startling the discus and stressing them out over time. (Fish very active at night may be the worst offenders.)
A few examples of fish falling into this category include larger clown loaches, red tail sharks, zebras, some danios, most barbs, some larger tetras, and others.

Some are known to be nippers, like Tiger Barbs, and that's a no-no for discus. Most Barbs are not appropriate except perhaps Cherry Barbs, which are quite peaceful.

Other fish that may not be suitable are large, aggressive fish (most other Cichlids), which can intimidate discus and out-compete them for food.
Some large Gouramis fall into this category. Angels can fall into this category too, at times, depending on the size of the Angels vs. the size of the Discus.

So, my point is, when selecting discus tankmates, do your homework - by checking out your selections' tolerance for a wider temperature range, their general behavior, compatability with others, and levels of activity, and whether they are nippers or have aggressive traits.
Amphibians like frogs are very likely to be unsuitable due to possibility of their harboring potentially harmful pathogens to discus, which the frogs are resistant to.
And they could tend to create messy water conditions.
Hope this gives you an idea of how to approach tankmate selection.
 
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