Any Reason To Do Water Changes When Water Chemistry Is Ok?

[eschaton]

My tanks are heavily planted, but mildly overstocked.

Everyone seems to be doing okay with a few exceptions: Some of the Corys have recently begun having eroded fins again, and a tiger barb has had a mild-case of pop-eye for a week plus which doesn't seem to be progressing.

I've been traveling so I've not gotten a chance to do a water change lately, whcih I will do tonight regardless. But Ammonia continues to read zero, as does Nitrite, and Nitrate remains fairly close to zero (plants must be sucking it all up).

Is there anything besides the nitrogen cycle which can require regular water changes? Or for future reference, will I be a-ok now my tanks are cycled provided the nitrate stays low as it has been?

 

[timmystood]

When water stats are fine the water changes be done less-frequently. However, water changes must be done at least every 2 weeks. The water stats might read zero but for the full benefit of the fishes health it must have regular water changes. There is nothing better for a fish than freshwater.

 

[jayjay]

There are lots of other minerals in the water that will need replacing and organic materials that will need removing.

 

[lljdma06]

Are you treating the barb with pop-eye? That is a treatable condition, you know. And there are many treatments available now that will help the barb without causing harm to the corys or the plants. I've successfully treated for pop-eye using Melafix at 1/2 strength, without causing harm to corys or plants. It should help with the cory fins as well.

As to your question regarding water changes, I'll say this. It's a cliche, but so very true. An ounce of prevention is worth a pound of cure. Do the water change.

llj

 

[eschaton]

Honestly, I've treated the barb with pop-eye once before when the tank was still cycling. It was for his other eye, and he survived, but lost his eye (another fish died during the same treatment regimin). He's not been the same since. While he eats, he's stunted and stays by the wall of the tank, only eating sinking tablets. He no longer interacts with the other Tiger Barbs in any way I can see. Just does is own thing

I also only have three Tigers, and as I've read more about them, I realized they aren't ideal community fish. Thankfully, only the big male has developed into a fin-nipper, and he only takes it out on the big female, not the tetras or danios in the tank. I don't have the tank space to restock a group of at least 7, and I have no way of telling if new additions to the tank will ignore the other species like the current ones are.

On top of this, the meds partially uncycled the tank. While it might seem heartless, I feel that treating him probably isn't worth it on the balance. He's small and sickly looking and probably had a reduced lifespan to begin with, and I'm worried that he'll end up surviving, but totally blind, at which point he'll probably be even more cautious, might need his own nano tank, and just might not end up eating at all.

 

[Bignose]

This is from a previous thread: http/www.fishforums.net/index.php?showtopic=157626

I wrote:

"
Firstly, your water's buffering capacity needs to be refreshed. The end products of the cycle are acidic, and given enough time without refreshing the buffers, your tank will drop in pH, sometimes very quickly. Given the other benefits of a water change, I feel the best buffer refresher is new water, instead of chemicals.

Secondly, there are tiny concentrations of all sort of other things in the tank that cannot be healthy for your fish. These chemicals are in the air and some of them do eventually make their way into your tank. I am talking about things like cooking oil, cigarette or candle smoke, carpet fumes, fumes from cleaning products, and many more. For people, all we have to do is open a window and clear the air. But, small concentrations of these get in the tank, part per million, parts per billion, maybe less, and for short times they probably have a negligible effect. But, if you don't change some water out, they sit in there, and build up, and I cannot imagine that they are good for the fish's long-term health.

Finally, for the sake of the fish, don't they always seem more perky and vibrant after a water change? During certain times of the year, every time I do a water change my corys respond with a spawning event. All the evidence I have ever seen shows that more water changes, the fish will respond will greater health and vitality. I keep fish to try to keep a little slice of nature in my home, and while it is impractical for most of us to do continuous water changes like nature provides, that water change is trying to approximate nature.
"

 

[highfire]

Also, although the water stats may be fine, the substrate will still need a clean. I find that my water is very stable, but the sand always looks as though it could do with a once over.

 

[karin15]

stay on top of water changes, don't w8 for your tank to start showing sighns of bad water quality.

 

[George Farmer]

You mention low nitrates. How heavily planted are you exactly? High lighting, CO2 etc? For an overstocked tank to exhibit low nitrates you need rampant plant growth. The fact that your fish are in poor health suggests that this is not the case. Heavily planted tanks rarely see poorly fish. I suggest your nitrate kit is duff, many are.

Water changes are good. Especially in overstocked, diseased tanks.

 

[Miss Wiggle]

You mention low nitrates. How heavily planted are you exactly? High lighting, CO2 etc? For an overstocked tank to exhibit low nitrates you need rampant plant growth. The fact that your fish are in poor health suggests that this is not the case. Heavily planted tanks rarely see poorly fish. I suggest your nitrate kit is duff, many are.

yup, nitrate kits are notoriously unreliable, you have to follow the instructions to the letter even then you can get 2/3 different readings from teh same sample of water, they also go off after about 6 months and need replacing.

get a new test kit

 

[dave_m13]

My Nitrates are always pretty low 5-10 now, I then change water, probably 25-30% every 2 weeks. I use half RO/tap water so this is the reason my nitrates do not go very high.

Before I was using RO, every 2 weeks the nitrates would be 20-30.