what next?

First, is the tank cycled? If your not sure please post your water readings (liquid test kit is best).

If the pump is too powerful it can stress them out and give them a disease such as ich...if this is an airpump you can add a gang valve and adjust the output, if this is a filter you can either a) put a prefilter over the intake or b) aim the output if it's a spray bar against the tanks back or side wall.

If these tetras are glass catfish, mine occupy the bottom layer...sometimes during feeding the LOW middle layer and adding more fish would be dependant on how many you've already added and what your planning on adding next. (I always try to add the peaceful fish first...such as corys, and then the more aggressive type fish last..such as tetras).

Again, if glass catfish some great suggestions would be marble or silver hatchetfish for the top layer...maybe some corydoras for the bottom layer being their nice for cleanup...and IF you like a bit of color against plants I've found that rasbora hets are stunning against the green plants and do well in low pH. Another gem of a fish is the dwarf honey gourami for that "pop" of color.

 

sounds like your cycled then, so that's a good thing!

seen it, but not familar with it...checked online and according to the mfr they recommend it for tanks up to 65g- which I don't know how they could recommend it for tanks that large when the gph is only stated as 185gph which is extremely low.

Being it sounds like yours is simply planted with "smaller" fish I'd go with at least 5x, so 40X5=at least 200gph. So at 185gph your pretty close to your range with that filter--and be aware that the mfr usually lie about the gph, or rate it WITHOUT media...media will decrease your gph.

BUT For optimal filtration you'd want 10x your tank volume for the gph. So say your tank truly is 40gallons, then you take 40x10= 400gph. I go with the 10x formula for tanks that are overstocked or contain large fish that produce alotta waste. Overkill in regards to filtration is always a good thing, unless you have something like a betta.

Gently waving is fine!
But just know that for instances of overkill filtration, or simply a filter with a powerful outtake that you can do a couple things which will help to reduce the flow:
1) aim the outtake towards the back wall or corner
2) add a spraybar, if still too powerful enlargen the spraybars holes with a drill or knife tip
3) prefilter the intake (sponge)...Prefilters are always a good thing and help to protect your filter, plus they give the added benefit of colonizing beneficial bacteria!

If your not adding co2 then the bubble wand is fine, actually helpful, but if your adding co2 you'll probably want to nix it being it will diffuse the co2. When adding co2 you want as little surface disturbance as possible.

Glowlights usually stay towards the bottom to low middle layer, at this that's always been my experience with them. Do they show any signs of "gasping" at the surface or any appearance of "salted" look? Also, what are you keeping the temperature at?

What are you feeding them?
IF you don't "see" them eating you can try something different. The food may be too big for them. Try something that's targeted towards small fish (New Life Spectrum Small Fish Formula is something that comes to mind).
http://www.google.com/products/catalog? ... GYQ8wIwAg#

Mine normally eat flake food (sometimes crushed into smaller pieces depending on the brand/type), frozen bloodworms (yep, I'm amazed they can fit the strands into their tiny mouths), and both fresh and frozen baby brine shrimp/artemia.

Sounds good to me as long as it's reading stable and the water temp is consistent (ie. heater).

With the proper parameters they shouldn't take long to get adjusted, and being there's no other inhabitants I'd say within 24hours at the most.

Good!

Lightings tricky, if their in the 6700K range then their good! If their actinics, then their useless for your purposes. IF the tanks not super tall and the lights getting down to the bottom you should be fine for low light plants- things like crypts, java ferns, etc.

If it's been at least a week, the fish you already have in there are adjusted, and the parameters are testing stable then you should be fine..BUT (sorry, I know that's not what you wanted to hear)...
The only thing that worries me a bit is you stating that the fish are staying at the top corner..which is usually a sign of lack of oxygen. Please post the water temps (thinking maybe the water is too warm). Also, in regards to the tetras ...is their coloration good (stripe vivid)?
Really the only time you should see them at the top is feeding time ime.

This may help you find the real size of the tank you have-->
http://elmersaquarium.com/h100tankchart.htm
We used to have a forum calculator for volume, it was lost during one of the many upgrades. I'll have to nag Anthony to see if we can get it back up

 

here's a link to my old setup with the glowlights to give you an idea of what healthy ones should look like. In the one photo you can see the bubbles from the spraybar (strong current) which they were swimming straight through with no issues whatsoever.

 

Bottom of the tank is good, that's where they normally hang out and their a schooling fish so being clustered is normal too. As for not eating, I'd try something like fresh hatched brine shrimp...they should actively chase it...if you can't get that then try crushing the flake a bit between two fingers and see if they'll eat it that way (or give a spirulina flake a whirl).

Yep, I can't see a problem with opening the filter up to full force...if it's swirling them around then you know to turn it back some or aim it at a back wall.

As for not moving around a lot, glowlights aren't a zippy type of fish (like a danio).

10,000K might give ya algae issues, just keep an eye out...i know whatcha mean with being bright...should see my 90g light with all 4 banks on..thing will blind you!

what other kind of fish are you planning on keeping with them??
(denison barbs, rasbora hets, neon tetras, soo many options!)

If your planning on staying with the tetra family they'll do best in a low pH...mine do amazing and even spawn at 6.0 with the temp at 83F (I have them with discus, hence the high temp).

 

water changes should be done weekly, at aprox. 25% of the tanks volume. your spot on about making sure the water temperature is close to the existing water..if looking to spawn then make it about 2-3degrees cooler than the existing tank.

Don't forget when adding "clean" water to be sure to use a proper baddy remover (if necessary- I'm not familar with the readings of well water as I have city water) BEFORE adding the new water. (I use seachem prime, only takes a little bit and works immediately so no need to "wait").

What's your pH reading? That will help with fish recommendations. If your wanting to stay within the tetra family their pH is typically low (6.0)..not saying they can't "adjust" to a higher pH, just saying they'd do best for ya in the long run with a low pH- and pH isn't really something you want to get into adjusting imo.

Your right about the mollies and platies being better with a lightly salted tank, plus you'll have to deal with live babies which will/can cause your tank to become quickly overloaded...which will lead to a heavier bio load not to mention water parameter fluctiations-ammonia from the births...blah blah blah.

Again, your pH would help me give some suggestions but a few that might interest you would be maybe some hi-fin corydoras for bottom feeders, a nice school of neon tetras for a burst of neon blue color, A dwarf Gourami makes a nice show fish, or a couple dwarf honey gouramis are usually high mid- to top hoverers and a nice subdued lemony color, cherry barbs would provide a vibrant red and would look awesome against the greenery and are very active and somewhat of a aggressive feeder, Harlequin Rasboras would provide a nice amber color to the tank and they too stand out against greenery, Emperor tetras have a nice purpley color but can sometimes be difficult to adjust, if your a guppy fan you could do some fancy guppies (warning, if you don't keep strictly males you WILL end up with live fry)...

so as you can see you have lots of options depending if you want colorful fish/subdued more natural looking fish/active fish/more of a "lazy" slow swimming type of fish.

If you'd like visuals try browsing through here (I'm not quite finished with it yet, but theres alot of profiles already up)--> Aquatic Profiles to Setup your Fish Tank / Aquarium

If you'd like entire tank stocking suggestions take a look here (photos too)--> http://elmersaquarium.com/c106communityinfo.htm

 

Nope, 7.2 is tropical fish...so you'll have plenty of options.
Good idea to have it double checked ... your main goal with the pH is consistency and no swings.

Also, not sure if you have a background on the tank...but most will recommend either blue or black dependant upon what you're keeping. Backgrounds can also make the fish's color appear more dramatic or more subdued dependant upon color.

 

if the tanks reading stable parameter wise you should be able to add them now.
Can't say one type of cory is hardier than the other...it's more about which type/color/finnage that you find visually appealing...and then gotta factor in the cost.
Some like pandas, other hi-fin orange lazers, some large schools of the dwarfs, and some albinos.. see what I'm getting at.

You could start with 3, then if they do well for a week or so then you could add 3 more (best to add newbies shortly after your water change day imo). Corys are schooling and really do better in large groups, I really began to see a difference in them when I got my school up to 10.
For a tank your size I wouldn't add any fewer than 5 or 6 in total.

 

I've never kept multiple types, but others on here have and stated they have schooled together.
(to me, it usually looks nicer/more uniform when you have schools of the same type..but that's just my personal opinion).

 

betta's can work in a community tank... either 1 male or 1-a couple females.
But I've always found they do better as a species only tank and have found the females to be a bit aggressive (similar to a tetra..can be nippy).