Is this normal?

[SplitAces]

Hi all,
I'm getting back into the hobby after 30 years out of it. WOW, have discus changed! I'm sad to have missed out on it, but being on the road and taking care of discus didn't work out so well. At any rate, I'm no longer on the road, the kids are grown and living their own lives and I find myself at the point in life where I can honor the promise I made to myself so many years ago; that I would raise discus again someday. Apparently, discus aren't the only thing to change in the hobby; I can't find an undergravel filter anywhere. So I bought the canister filter I had always wanted; and it is pretty slick, practically silent and keeps the water sparkling clean, but... the output wand with all the holes in it doesn't agitate the surface, and my discus were hugging the surface like they couldn't get enough oxygen. I dropped an airstone into the tank and they're behaving normally again, but I have to ask, is this the norm with canister filters, or am I doing something wrong? It's only a twenty gallon tank with two juvenile discus, six neons and a couple of corys. The filter is a Sunsun Hw 302, 264gph; rated for up to 75gal. I don't think the tank could be considered overloaded. I also dipped in a 5 in 1 test strip and all was well. I'm fairly certain I'm making a big deal out of nothing, but I've never needed to use an airstone with a HOB filter.
Thanks for your help,
Steve

[Phillydubs]

I always use a sponge filter with an air pump as well as an hob. You may want to try and adjust the bar or the output so that it moves water at the surface and breaks the top so the water is circulating...

All of that being said... Welcome back to the hobby but your set up is not at all ideal for discus unless you had a breeding pair by themselves. Discus are schooling fish and do best in groups 2 in a twenty with tank mates will prob not end pretty...

[1077]

If output wand with all the holes or (spraybar) as they are called, attaches to the glass with suction cups,then raising the wand/spraybar higher on the glass to just below the surface of the water will increase surface ripple and help with oxygen exchange.
Wile Discus are comfortable at higher temp's 82 to 86 degree's F,the neon's and cory's will not appreciate the temp's over the long haul.
Sterbai corydora's are most often suggested for Discus tank's as they are more tolerable of the higher temp's than most of the other corydoras species.
Cardinal tetra's and rummynose tetra's are most often found in Discus tank's for same reason. (heat tolerable).

[MD.David]

I have always had an air stone with HOB, however... the last several years I have used only sponge hydro filter with air stone inside.
I have found that HOB or canister filters can bread a nitrite explosion, if you don't keep up on cleaning it regularly.
Personally I had an explosion a few years go, was my own fault, but I switched to hydro sponge after I cleaned up my tank.
Now all I have in my tank is sponge filter and heater, zero substrate or anything else.
My discus are giants and I have yet to see their equal, besides at shows.
Tank only, ultra sterile environment does make a difference.
I have tried the HOB, canister and all in between, sponge filter is by far the best, mostly because it forces you do to water changes and vacuum the tank daily.
If your using house tap water, get a nice two or three stage filter inline. You want your tap water being very sterile.
If you get healthy fish and don't introduce any illnesses, your fish will grow and live for 10-15 years.
The discus can really captivate a person's soul.

[SplitAces]

Thanks for your advise. The twenty gal. tank is just to get started. I already have a 75G and a 55g tank as well. I have some rearranging to do before I have a good place for them.

[SplitAces]

Thanks for the proper nomenclature to describe what I mean. I really got the neons and corys just to get the tank going. I find I'm so beguiled by the discus that I rarely notice the other fish. The discus are even more heat tolerant than most people realize. I once got eighteen 3 to 5 inch wild caught discus from a pet store in Miami for $10 because they were so fungused that they looked like swimming cotton balls and they were all dying. Got them home and put them in a spare tank and ran the temp up to 104 degrees, which killed the fungus, but not the discus. Well I did lose one, but it was in very bad condition, even compared to the rest of them. This was back in 1985 and I don't remember how long it took. I believe it was a day or two at least.

[SplitAces]

It sounds like you have been religious with your water changes to have such large discus. I just hate the look of the sponge filter. I'm thinking I'll use my 55g as a sump for my 75g tank. That way I can do all the filtering in the sump and keep it out of sight; and the discus could have the equivalent of a 130g tank. Have you posted any pics of your discus?

[MD.David]

Here is a good picture you can see the size of Mr.fathead.
This is a 120g I just threw some Ken's immune booster flake in.
https://s32.postimg.org/9xyi973c1/IMG_20160712_095730855.jpg (https://postimg.org/image/9xyi973c1/)

[SplitAces]

Wow very nice! All of a sudden, my 75g doesn't look nearly big enough. I can't get over all the new strains available now. Pigeon bloods were just making an appearence when I got out of the hobby, and I hated them; thought they were butt ugly compared to a Wattley's turquoise. Thank Goodness the East didn't agree with me!