Filter 9 gallon betta tank

I am currently setting up my first tank in 35 years or so. I'll be getting a plakat once the tank is ready. It's had plants for about a month. Once I get the plants right, I'm going to do a fish in cycle with male guppies a friend who has millions of them is going to loan me for this purpose. Once I have two male guppies living happily in this tank, I'll give them back and get a betta from a local fish store,

I am having trouble figuring out what to do about the filter. These tanks have a built in filter that takes up about 1 1/2 gallons out of 9. There's a lot of empty space in it that I have filled with ceramic biomedia and course sponge.

These tanks have a lot of flow and a pump you can't adjust. There is a tube about 8 inches long between the pump and the water outflow. In order to slow the flow while keeping the filtration, I cut a hole in the tube near the top. Water will exit through this hole and flow over biomedia before the pump takes it up again.

Even with this modification, there is still to much flow for a betta, according to what I read. I can put pieces of sponge in the outflow tube to slow in further. In fact, I can slow it to almost nothing if I chose.

I also have an airstone in the corner farthest away from the filter outflow turned very low. This is cause my partner likes it.

Once I get the guppies out of there, I guess I'll slow it way down and rely on water to test to indicate if I have enough filtration. I stand ready to do water changes as often as needed as I figure this out.

If any of you have any advice I'd like to hear it.

 

You could use floating plants as filtration like in the bettas natural environment. Duckweed can be found in about any pond and along with a lillypad it has kept water crystal clear for me in the past. Floating plants are fine for bettas as they don't require much oxygen plus an airstone will give more than enough

 

I put some frogbit in recently and it's starting to grow. Also have a couple of crypts and an anubius.

 

I put some frogbit in recently and it's starting to grow. Also have a couple of crypts and an anubius.

I have an anubius and the fish love it. It's like a minI forest under those leavesgood luck with the tank!

 

I assume you've got the fluval 9? It's a great tank, though I do wish it had the adjustable flow that the spec 5 has. You can angle the flow heads to the wall and put something in front of it, including plants.

Elodea aka Anachris is a fantastic one for the betta tanks and the fluvals, I can finagle them in front of the flow to lessen it's push but still allowing the betta to have a resting spot at night off to the side. I used to loathe the look of it in tanks but it's been one of my favorites recently due to it's growth rate and benefit to fish and tanks.
Anubias is awesome and echinodorus can be a great addition, wonderful long leaves.

I guess I'd avoid putting sponges in the filter tubing, but that's partly because I've had to take apart that filter once already when it got clogged up and I wasn't thrilled about it - adding sponge just seems like it would complicate things. You can also add some sponge filter to the intakes on the top and bottom, could slow the pull and it definitely keeps my shrimp from getting back to the heater area.

 

Right, Fluval Flex9. I bought the 9 for a betta and the 15 for a community tank.

Thanks for the responses.