Filter to choose for a tank approx 680x440x400mm tank

[Ice222]

Basically I'm planning to have a display planted community tank customed and plan to stock:

Definitely stocking-

1 x Betta

15-30 x CPDs (depending how many I manage to breed)

5 x Oto cats

5 x Pygmy cories or salt&pepper cories (depending on what's available in NZ?)

Most likely also-

5 x Kuhli Loaches

3 x Sparkling gourami (will test with the betta, if they don't get along, then they'll stay in separate tanks)

As for plants, the main 'difficult' plants I want to grow are glosso and hairgrass. I read that these plants prefer good filtration and good water circulation or they'd be prone to algae, they also need good lighting but I should have that sorted. I should be able to create some darker areas for the Pygmy cories by using taller plants if I do end up getting them.

The current plan is for a 680W x 440D x 400Hmm tank ie about 120L. I haven't had the tank made yet, so the sizes are still adjustable, and I'm willing to go up to 720W x 480D x 420Hmm (about 145L), and I probably will. The problem is, is there such a thing as 'too much filtration'? I'm quite keen on the Fluval 204 or the Eheim Pro 2224, but I was told it might be too much for such a small tank, and to go for a Eheim 2213 instead. Now, I'm kinda inclined to believe them, since it was a retailer that told me that, and you'd think they'd what you to buy the more expensive product :lol:. Plus with the betta, even with him being a plakat, I hear they don't like too much flow/current. I will have a sponge filter piece over the intake btw, so I shouldn't have to worry about my tiny fish getting sucked in.

Anyway, please let me know what filter you'd recommend, and the reasons. I hope my stocking levels and types aren't too incompatible to work I did check with AQ Advisor beforehand, and it stated that some of the temp ranges for the fish aren't compatible, but I believe that CPDs would be fine at the 25C temp that the others may need.

[the-obstacle]

I wouldn't have thought there'd be too much of an issue with overfiltration. I'm running a 2224 on a 75L tank and it's fine. Good current if you open it all the way up but I have it on about half flow and it's enough to ripple the surface but not blow the plants down.

Is there such a thing as water that's too clear?

I guess the problems would come if you stripped the water with chem filtration and/or UV but I would have thought the bigger the better for basic mechanical and biological. At the end of the day the bacteria only grow to fit the amount of food they're being given so it'd be down to your stock levels that'd matter.

[Joshlikesfish]

I keep fighters in a tank with a lot of flow. Well flow in multiple places. They seem alright

[Ice222]

It's more whether the fish would be okay with the high flow/current created by the filter that worries me.

[phoenix44]

Get a filter that you think is a size too large for the tank, if you are happy to afford it.

Glosso needs very good and strong light.

You can regulate your flow with strategically placed pieces of driftwood etc.

[SamH]

Definitely go for a slightly larger filter, you can always weaken or block the flow if the fish aren't coping. The filter getting clogged will also lessen the strength of the flow. You're using your MG PK fighter yes? If so, he can deal with the flow just as well as any other fish.

HTH

[Ice222]

Get a filter that you think is a size too large for the tank, if you are happy to afford it.

Glosso needs very good and strong light.

You can regulate your flow with strategically placed pieces of driftwood etc.

I'm planning on getting the Hagen GLO T5 HO lighting system, the 60cm one, so I think that should be good enough. wish there was a size between 60cm and 90cm, but alas, light tubes and fixtures only come in set feet lengths .

And yea Sam, I'm going with my plakat most likely. He's good looking and well behaved, better stick with him than risk any other betta not getting along with my other fish .

[Joshlikesfish]

Ehiems have pretty low flow also I believe?