Why Are Water Changes Necessary?

[cameron]

Hello Everyone,
I was just wondering why everyone says that we need like 50% daily water changes for juvies, what are we trying to remove. For example if I have live plants and my ammonia and nitrite are constantly 0 and my nitrate remains under 5 for two weeks then what is the point of the water change? I'm just trying to get clarity because there seems to be a large agreement on the necessity of water changes but I haven't found a reason.

[Skip]

Hello Everyone,
I was just wondering why everyone says that we need like 50% daily water changes for juvies, what are we trying to remove. For example if I have live plants and my ammonia and nitrite are constantly 0 and my nitrate remains under 5 for two weeks then what is the point of the water change? I'm just trying to get clarity because there seems to be a large agreement on the necessity of water changes but I haven't found a reason.

cuz clean water is what is best for discus.. or daily at least 50% is the standard set by experience due to success and failures..
which i would think would be good enough reason

but if you want some kind of chemistry equation to PROVE it.. .. i will defer to someone else

[Allwin]

Water chemistry is not just H2O. It contains various minerals and molecules in it. Minerals normally gets depleted over the nitrification cycle process. So adding more water, thus increasing the minerals content inhibit the growth of the fishes imo.

[cameron]

Water chemistry is not just H2O. It contains various minerals and molecules in it. Minerals normally gets depleted over the nitrification cycle process. So adding more water, thus increasing the minerals content inhibit the growth of the fishes imo.

These are the trace elements the fish need? Would there be any way to dose these rather than doing large water changes to replace it.

[Allwin]

By doing wc, nitrates are reduced parallely as well and its easier to replace water rather than playing around with the depleted minerals ratio at the right level and combination, my few cents.

I would wait to see some experts reply as well.

[discuspaul]

I'll provide confirmation of what Skip said.

It has been proven over many years that discus thrive with large, frequent changes of fresh clean water.
Conversely, discus have shown to be intolerant of poor water quality & conditions, where they are much more prone to developing health issues.

The best way to provide high water quality and conditions is to give discus lots of large, frequent fresh water changes. It's as simple as that. There are many undesirable elements & conditions which can develop and accumulate in aquarium water if water changes are significantly neglected. Just because the water is clear, and there are no traces of ammonia & nitrates, and low nitrates, doesn't mean the water quality & conditions are good, especially when it comes to discus.

As to Allwin's comments, perhaps I misunderstood, but I'm not sure he meant to say what he did, or the way he said it.

To my knowledge, replenishing the mineral content with fresh water changes does not inhibit the growth of discus.
The only caveat is that if the water source already has a high mineral content, and that mineral content gets further increased with frequent water changes, then that could potentially be somewhat harmful to discus, if the mineral content gets exceedingly high.

[DiscusLoverJeff]

Adult discus disperse a lot of waste. And multiply that times the amount of fish in your tank. The waste fouls the water. Even the best filtration can only do so much. Foul water equals high ammonia and nitrates. Ever heard of nitrate poisoning? Discus are very sensitive fish as well; so the little things like lack of water changes can effect their system. This in-turn can cause disease and other issues.

Yes, discus owners do a lot of extra things like water changes to protect and keep the fish happy and healthy. Clean water equates to larger fish, good color, hearty appetites. Simple really.

[John_Nicholson]

If you ever tried to raise discus without the water changes you will understand...At least you will if you ever see nice, healthy discus. I have known a few people who thought their 4 inch, poorly shaped discus were nice.

-john

[Allwin]

As to Allwin's comments, perhaps I misunderstood, but I'm not sure he meant to say what he did, or the way he said it.

To my knowledge, replenishing the mineral content with fresh water changes does not inhibit the growth of discus.
THe only caveat is that if the water source already has a high mineral content, and that mineral content gets further increased with frequent water changes, then that could potentially be somewhat harmful to discus, if the mineral content gets exceedingly high.

Paul, Minerals/Elements in the water at optimum ratio are important to the fish growth.

[DiscusLoverJeff]

Paul, Minerals/Elements in the water at optimum ratio are important to the fish growth.

That is why we test our water frequently!

[discuspaul]

Paul, Minerals/Elements in the water at optimum ratio are important to the fish growth.

I agree Allwin - but that's not what I understood you to say.
Your comment was, quote:
"So adding more water, thus increasing the minerals content inhibit the growth of the fishes..."

Isn't that contradictory to what you said in the quote just above ?
On the one hand you said increasing the minerals content inhibits the growth of fishes, and on the other hand you're saying minerals are important to fish growth, the latter with which I agree.

I certainly don't mean to offend, or belabor the issue, but have I misunderstood your words or meaning ?

[Snow]

So, wouldn't the large frequent water changes cause your tank to cycle or go thru a mini cycle every time? Just curious about this......I wonder about it every time I do water changes now (which are most days....I find it relaxing...weird I know...but it's my wind down time).

[Allwin]

Np, doesn't mean to say "add more minerals for fish growth". Mean to say adding more fresh water will replace the depleted minerals.

I agree Allwin - but that's not what I understood you to say.
Your comment was, quote:
"So adding more water, thus increasing the minerals content inhibit the growth of the fishes..."

Isn't that contradictory to what you said in the quote just above ?
On the one hand you said increasing the minerals content inhibits the growth of fishes, and on the other hand you're saying minerals are important to fish growth, the latter with which I agree.

I certainly don't mean to offend, or belabor the issue, but have I misunderstood your words or meaning ?

[Keith Perkins]

So, wouldn't the large frequent water changes cause your tank to cycle or go thru a mini cycle every time? Just curious about this......I wonder about it every time I do water changes now (which are most days....I find it relaxing...weird I know...but it's my wind down time).

No, at least not if you a mature tank with healthy biological filtration. The one thing I haven't seen mentioned in this thread is bacteria. You can do all the standard aquarium water tests daily and not detect bacteria problems in your tank. I know the OP started this discussion about juvies, but anyone who raises fry will tell you frequent WCs and tank wipe downs prevent bacterial problems.

[cameron]

Ok thanks for the advice guys. I was just curious. I am planning on having a 55 gallon tank with 6 juvie discus (~3") (because that is all I can afford) and I will be doing twice weekly 70% water changes with wipe downs. Some people have said that with juvie discus like that you should do daily water changes and I just don't have the time to do that. Does this mean that I can't keep discus? So I just asked this question because I was confused about why the frequent water changes were so necessary and whether a lack of frequent water changes meant I couldn't keep discus.


The tank will be bare bottom with some driftwood and plants just to make it look more natural and provide the discus with filtration. The filtration will consist of dual Hydro 5 Pro sponge filters & an Aquaclear 70.