[fishkeeper01]

So for a 2g betta tank with no filter, how often Sikhs the water need to be changed?

 

[H2Ogal]

I've tried small filterless tanks for bettas and IMO it's best to do small (10%-ish) water changes daily. Some people change 100% of the water weekly, but I can't help but think that's stressful for the fish as ammonia will build up all week long plus a 100% WC may cause damaging swings in temp and pH.

You perhaps already know this, but I'll mention it for others who may not: Bettas can survive in unfiltered tanks because they can gulp air at the surface, so the lack of water flow/oxygenation won't kill them -- but ammonia in the water will burn their gills and do other damage just the same as with non-labyrinth fish. Bettas really do best in filtered, cycled tanks. And, being tropicals, they do need a heater. For a tank that size, a 25w heater (or smaller if you can find one) willl do nicely.

 

[fishkeeper01]

Another question, I'm looking at upgrading to a 20 long and dividing it for multiple males. If I use a filter will the surface agitation cause them to not make bubble nests. I don't plan on breeding them, but have i heard they can get stressed from having to much water movement and not being able to make nests.

 

[lauraleellbp]

Let's pick a random number and say that waste from your betta produces 0.10 ppm nitrates per day in your nano tank.

Do a 10% water change and you are left with 0.09 ppm immediately after the change. 24 hours later, that will be 0.19 ppm.

Remove 10% and you're left with approx 0.17 ppm immediately after the water change.

By the following day, the tank water is at 0.27 ppm. Minus 10% leaves 0.24 ppm, which by the following day is 0.34 ppm.

And so on and so forth.

Bottom line- all other factors remaining the same, with the same amount of waste being produced every day, you must change over 50% of a tank's water to do anything other than maintain equilibrium.

The necessity for big water changes boils down to simple math.

 

[Fishumms]

2.5 gallon tank I've had for about 10 months. It is heavily planted with immersed plant, can't see in the picture. I do a 50% maybe less once a week water change. There are also 2 sulawesi snails. It is "dirted". I believe the plants make the difference. They grow very fast. Floaters in particular. It generates enough duckweed to fill my 75 gallon pond on a regular basis.

Also, it has a heater but no filter.

 

[fishkeeper01]

Will they get stressed if there I'd surface agitation and they are unable to make bubble nests?

 

[AGUILAR3]

I have 11 Bettas and 3 have yet to make a bubble nest in over 6 months. Some bettas go their whole life never making a nest. Don't be fooled by those who say a Betta blows bubbles only when it is happy and conditions are ideal. Even a sick and dying Betta living in poison will make a bubble nest....it's instinctual.

 

[AGUILAR3]

....and yes, some bettas absolutely hate current while some embrace it. Most hate it though.

 

[fishkeeper01]

So would a sponge filter be better than an hob filter?

 

[umarnasir335]

Sponge filters work really well for tanks 5 gallons or smaller.
I run sponge filters on a divided 4 gallon, a 3 gallon shrimp tank, and 2 for my 20 tall, and do only weekly 50 percent water changes. Of course, plants help with the nitrates

Also, most bettas dislike HOB filters, especially on smaller tanks.

 

[H2Ogal]

Another question, I'm looking at upgrading to a 20 long and dividing it for multiple males.

So would a sponge filter be better than an hob filter?

Sponge filters work really well for tanks 5 gallons or smaller.
I run sponge filters on a divided 4 gallon, a 3 gallon shrimp tank, and 2 for my 20 tall, and do only weekly 50 percent water changes. Of course, plants help with the nitrates

Also, most bettas dislike HOB filters, especially on smaller tanks.

I had a divided 10g with a HOB. I used tubing to extend the intake so it could be placed on the opposite side of the divider from the outflow in an attempt to make sure that all water in the tank would be filtered. Even with adjustable flow on the HOB, the water movement was decidedly different on the two sides, and I can't say that both bettas were equally happy. Long story short, I lost one fish shortly after, so my dual tank wasn't set up for very long. If I had it to do again, though, I would set up with a sponge filter for each section as umarnasir335 recommends.

 

[H2Ogal]

2.5 gallon tank I've had for about 10 months. It is heavily planted with immersed plant, can't see in the picture. I do a 50% maybe less once a week water change. There are also 2 sulawesi snails. It is "dirted". I believe the plants make the difference. They grow very fast. Floaters in particular. It generates enough duckweed to fill my 75 gallon pond on a regular basis.

Also, it has a heater but no filter.

Beautiful tank and betta, Fishumms. You're right about fast-growing plants helping with water quality. So you grow the duckweed for your pond on purpose? Do you have goldies or something in the pond that eats it?

I'm still a fan of having a heater to help maintain temp, but if the room stays warm enough, some people go without them in tiny tanks.

 

[AquaAurora]

My betta is currently living in a 20g long with an aquaclear 70 hob. i have a piece of foam over the outflow to keep agitation down for the betta and the sand substrate, but I loosen it once in a while to let some decent flow through to deal with surface scum. The betta can't win against the stronger current, but even though he can get/stay away from it he will hang out by the hob when he wants. I think he thinks the whole tank is all his "and I'll be damned if I let a little current get in my way!" He also likes to eat anything he sees the otos eating (busted him going to town on zucchini).

 

[fishkeeper01]

Well cuz I'm looking at getting a 20 long and dividing it into five sections. So I was wondering how one would filter that.

 

[Skeetz]

i would filter it with a tetra "whisper 10i" filter. they do not make much current. i have one in my ten gallon and it makes what looks like its(the filter's) own bubble nest

 

[umarnasir335]

i would filter it with a tetra "whisper 10i" filter. they do not make much current. i have one in my ten gallon and it makes what looks like its(the filter's) own bubble nest

This is a good idea and the filter itself is great, but it isn't fully adjustable.

Maybe try an air pump (the whisper 10 gallon will work) and buy 3 of these:
Amazon.com: Jardin Fish Aquarium Mini Cylinder Soft Sponge Water Filter, Black: Pet Supplies

You'll get enough filtration for all 5 bettas, good water movement. They key will be to put a 3 way gang valve on the intake of the air pump to control the power of the flow of each sponge filter

Gang valve: Amazon.com : JW Pet Company Accuair 3-Way Aquarium Gang Valve : Aquarium Air Pump Accessories : Pet Supplies

 

[fishkeeper01]

So are you suggesting one tetra whisper for the whole tank, or for each section put a whisper filter?

 

[amcoffeegirl]

I have finnex pf-5 on two of my bettas tanks they don't mind. In my spec 5 the male blows bubbles all the time. Some people say that filter is too strong for bettas but he's a plakat.

 

[fishkeeper01]

So I wouldn't need a filter for each section?

 

[umarnasir335]

Either keep one 10-20 gallon sponge filter, or 3 smaller 3-gallon ones from the links I wrote down. You will need an airpump for the sponge filters though.

The good thing is that the whisper filters usually come with airpumps, albeit smaller ones.