Water movement

[9tails]

Can anyone give me pointers on how much water movement I should have in my tank?

I've moved my filter pipe so that the water pumps against the back of the tank wall, this is less noisy than when it was splashing on the top of the water. I've noticed that the water in the tank moves really fast now, there is a strong current in the tank and the fish look like they are "swimming upstream". Could this stress the fish, should I find a solution to slow the current down or will they not mind?

The tank is 33 gallons, the fish are 8 guppies, 3 swordtails, 4 minnows, 4 danios, 3 cories, 2 bristlenoses and 3 barbs.

[daveedka]

It largely depends on the type of fish, and most of the fish you've listed appreciate current, the rest shouldn't have a problem with it. Guppies IME tend to enjoy swimming against the current ( just an observation not a documented fact), pleco's like current, and danios move too fast to care :D .
If you see your fish hiding a lot or congregating in the corner of the tank, I would say you have too much otherwise I wouldn't worry about it. If you want to reduce water movement or disperse current, T your return into a pvc tube and drill small holes the length of the tube, then you can experiment with different hole placement to get exactly what you want. DIY diffusers are cheap easy and IMO fun to mess with. you can also attach a sponge to your return to diffuse the waterflow a bit.

[9tails]

Thanks for your reply, daveedka. For aesthetic value, I prefer the setup because the plants sway in the current.

I'm sure you're right, I watch the danios and guppies swimming against the current, getting to the source of the flow, then letting the current "whoosh" them back from where they came then they do it all over again. I reckon it's their version of the Big Dipper!

[daveedka]

Yeah, the guppies kind of suprised me because I i understand correctly they don't come from fast moving habitat Their primary food source in the wild is misquito larvae, which leads me to believe they live in fairly calm pools, my guppy tank is grossly overfiltered by design, and they seem to always congregate at the filter output to play, and only go to the calmer areas of the tank for sleeping and feeding. Wierd I guess.

[Hydro]

White Cloud Minnows, if that's the type you have, also enjoy currents. Their natural habitats are fast flowing mountain streams.

[9tails]

They're called golden minnows, yellow bodies with red fins. But they're the same shape as the white clouds, so I'm sure they're just the same model but different colour.