Water Changes?

[salman]

How many water changes do you do per week?
I do a 15% water change daily for my discus which is 105% per week.

All my other tanks i do a 10% per week.

[zqia014]

depends on your water quality.

For your discus tank if you water quality can be maintained, ie. no ammonia, nitrite and very low nitrate, you don't have to do water changes that often.

I normally 15% each week.

[Zerileous]

I do 3 gallons weekly (on a 10 gallon)

[salman]

depends on your water quality.

For your discus tank if you water quality can be maintained, ie. no ammonia, nitrite and very low nitrate, you don't have to do water changes that often.

I normally 15% each week.

I have no ammonia, no nitrite, and very low nitrate. But i do water changes this often because i like this tank to be perfect because its in my room.

[Drumachine09]

I do 50% on my 10g nano every 2-3 weeks, at least 50% on my 55 every week, and 50% on my 10g livebearer tank every week.


Basically, do as much as you can as often as you can.

[zqia014]

I have no ammonia, no nitrite, and very low nitrate. But i do water changes this often because i like this tank to be perfect because its in my room.

I think it's unneccessary to change if on a daily basis if you have good water quality, you discus might be more stressed because there are daily changes to its water parameter, not big changes of course.

[nanaglen2001]

I do a weekly waterchange about 50 to 70 % on my big but overstocked Central American tank.

My other 3 smaller tanks get a 75 % change every 2 weeks.

Thank heaven in Germany we have no chlorine in the tab water, so I just can pour the water in, without any fuss.

[Lady Hobbs]

I do 50% on my 30 and 55 gallon tanks. A bit less on the other two smaller ones.

[RobbieG]

50% on all of them every week!

[Kuli_Loach]

I have been doing a 50% every 5 days on my 10 gallon hospital, and 10 gallons every 3 on my 55 to keep the nitrites down.

[dev]

I change 30% once per week with a 2-way hose for my tanks, unless there is reason to break the routine.

Fry tanks get smaller and more frequent changes using a bucket.

Btw. A daily water change of 15% does not equal a 105% weekly water change.

Day 1 - You have 100% original water
Day 2 - You have 85% old water, and 15% from yesterday
Day 3 - 72.3%
Day 4 - 61.4%
Day 5 - 52.2%
Day 6 - 44.4%
Day 7 - 47.7% from last week, and 62.3% added this week

So 7 days with 15% water change is closer to one 50% water change, allthough the 15% routine should be better for your fish.

The point is that if you had 50 ppm nitrates on monday, you will have 24 ppm on sunday, plus some new nitrates from this week.

[salman]

I change 30% once per week with a 2-way hose for my tanks, unless there is reason to break the routine.

Fry tanks get smaller and more frequent changes using a bucket.

Btw. A daily water change of 15% does not equal a 105% weekly water change.

Day 1 - You have 100% original water
Day 2 - You have 85% old water, and 15% from yesterday
Day 3 - 72.3%
Day 4 - 61.4%
Day 5 - 52.2%
Day 6 - 44.4%
Day 7 - 47.7% from last week, and 62.3% added this week

So 7 days with 15% water change is closer to one 50% water change, allthough the 15% routine should be better for your fish.

The point is that if you had 50 ppm nitrates on monday, you will have 24 ppm on sunday, plus some new nitrates from this week.

I dont get it..

[Bill M.]

I do a 50% WC on my 29 and 10 gallon every week. It only takes like... 30 min to do both, thanks to my python... hehe

[dev]

I dont get it..

It's just that the new water you put in will mix with the old water. So next time you change water, you can't do it in a way so you only take out water from last week.

Heres' a graph showing how the nitrate level develope in a tank with different water changing schedules. This graph assumes your tank produces 1 ppm of nitrate per day, but the concept is the same for any tank.

I was really making these for a seperate thread on choosing water change schedules, but here you go :)

[Only Registered Users Can See Links.]

[dev]

Today I heard a very good illustration of the difference between two 50% water changes, and one 100% waterchange.

If you fill a glass with urine, would you rather do one 100% water change, or two 50% water changes before you drink the content? :D

It didn't take the guy very long to figure out that two 50% ones would leave him with 25% urine in the glass.

[salman]

oh ahhahaha! that kinda made it clear,

But what i meant by the 105, was 15 x 7 the sum of the water changes.

[Drumachine09]

Today I heard a very good illustration of the difference between two 50% water changes, and one 100% waterchange.

If you fill a glass with urine, would you rather do one 100% water change, or two 50% water changes before you drink the content? :D

(I suggest the 100% water change, as two 50% ones will leave you with 25% urine in the glass).



Haha, well that was a colorful explaination! lol

[dev]

oh ahhahaha! that kinda made it clear,

But what i meant by the 105, was 15 x 7 the sum of the water changes.

*nod* Yes, I thought that was what you meant. I just wanted to point out that while you carry a lot of water around, you are only removing about 50% of the contaminants per week - which, of course, should be more than enough..

Haha, well that was a colorful explaination! lol

hehe, yes. But it sure did get the guy thinking :)

[MeganL3985]

Hahahahaha I love that explanation!