How often should I do water changes?

[Betta man]

I have a pond outside and it has one comet goldfish in it with some java moss. It's probably about 45 gallons. How often should I do water changes on it? I also have my 15 gallon with 5 pure betta imbellis, an imbellis x splendens hybrid, and a pair of wild type poecillia wingei. It has a tetra 15 filter and a whisper quiet flow 20 along with a fluval sponge filter in it and some red ludwigia and Italian Vallisneria and java moss. Every time I go to do a water change, the water is really filthy looking. I do water changes about once every two weeks and it keeps surprising me that it's so filthy. What would your recommendations be for water changes? I don't think I can do more than one water change per week, and it seems to me that I should only have to do it once every 2 weeks. Thanks!

[FRIENDLYFISHIES]

I always do more than necessary to keep my water in good condition, I personally would do twice a week, but if once a week is the minimum you can offer, I would do the once a week, but thats me. I like to put myself in the fishes fins and think, "How would I like my environment to be?" lol. I know cycled tanks and others let their tanks go much longer, but I just couldnt bring myself to do it. In my limited experience it only takes that one extra day to mess things up or ill my boys.

[Betta man]

It grows a little bit of brown algae. The way I figure, all you need for a betta is 2 gallons per fish. Endlers should need about 3 gallons for a pair as they are small fish. I have over double the filtration too. The water looks clean while it's in the tank but once siphoned out, it looks dirty and has detritus in it.

[lohachata]

30% water changes each and every week........

[BettaGuy]

Once weekly like loha said, even though when it is planted I would change a bigger amount (maybe 40-50%) each week because the plants need the micro nutrients in the new water for food. I would say your water looks clean, but is dirty when you siphon it out because you suck up poop that was resting on the bottom when you clean. Since the poop doesn't float around in the tank it looks clean, but when you suck it out it looks dirty.

[Betta man]

Okay. Thanks loha!!! I'll try that.

[FRIENDLYFISHIES]

lol I just saw that I forgot to put my %...I simply said change, sorry. Yes the others sound good. If it were me id personally do 2 weekly, 1 20-30% water change and 1 50% using a gravel vac, but thats me, as I said, I over do it lol =P

infact I just did a water change on my 10 gal, its been running for maybe a week with one male betta, 2 snails and live plants...I cant believe the mess they made! lol. Ammonia 0 but still when I went moving things around with the vac, plant roots, snail poops and betta poop floating all over the place I think the snails made the bigger mess though.

[Betta man]

Try keeping 6 bettas and 2 endlers in a 15 gal. It's really messy. I haven't had any problems with water parameters because of the plants and extra filtration, but it always has detritus at the bottom. Maybe sometime I'll enter a pic of my tank in TOTM. It's next to a fry tank and it's hard to keep the fry tank out of the pic.

[lohachata]

try keeping 200 common plecos in a 20 long.....

[Betta man]

No thank you. Sounds too hard. I'll stick to bettas.