changing 100% a month

[2639]

Is changing tank water 100% every 30 days simply wasting the elements in the water?

I am considering doing a 1/30 th water change per day which is 100 % every 30 days ( 3 gallons a day ) to maybe try and keep things more level. I saw a graph that mr. Farley did regarding MG and the smoothest curve was when things were doine on a daily basis.

I am just wondering how silly this is.

Any opinions?

 

[Mr31415]

Unless you automate this it will be a PITA. My personal opinion? I think too much water changes is a waste...

 

[waldomas]

Actually, this isnt 100 percent change per month. As the days go on, you change out more of the water you already changed! You would be MUCH better off changing 20 gal / wk.

 

[geekreef_05]

First of all, 100% WC's are very stressful to your inhabitants. Although there are reef experts that use this method, it just logically doesnt equate to happy inhabitants.

Second, doing daily water changes sounds like a waste of time, money, energy, etc. Unless you can automate the process of course, and even then Id question the usefulness.

Your water change schedual should reflect your bioload, water volume, feeding habits, maintaince habits (carbon, etc) and all the rest. Water changes are something you have to 'feel out' because no one can tell you whats right for your reef.

I could, however give you a great rule of thumb...which would be to change about 30% a week.

 

[2639]

Great info guys!
if I do 30% a week, that's more than 100% a month. That contradicts what your first statement says ( unless I'm misunderstanding that )


Right now, I do 20 gallons a week which isROUGHLY 100% a month for me.

I honestly had no idea that was more stressfull on the critters I DID however have a feeling it was a waste of money and time LOL

Thanks for the heads up everyone. I'll stick to my current schedule for now

 

[Randall_James]

100% water changes will not hurt a thing so long as you match salinity and temp... I change 100% per month myself but do it 25% a week. Just a lot easier to deal with and it allows me to blow out the rocks more often.

Waiting 30 days between wc's I think creates too large a swing in water quality, smaller more frequent in this case are less stressful IMO.

Is this an excessive amount of water changes? yea probably,

worth it?

Most certainly... I purchase no tank supplements, I purchase no test kits (hey with that much water changing, what could build up?) I have not now or ever had cyano, algae or any other issue to deal with that originates from excessive nutrient in the water column.

If you have the time and patience to do these changes, go for it...

Cost wise it is about a wash, test kits (good ones) are expensive as are other supplements. Test kits have a definite shelf life and they do no good if they are inaccurate. If you have a lot of calcium hungry stuff, Red Sea salt has a bit higher level of CA than say IO salt.

 

[2639]

maybe i mislead you all..I didn't mean wait until the first of each month and do a 100% in one day..nonono

I meanth spread that out over 30 days: 1/30th a day ( in my situation that's 3 gallons a day. ).

I can truly see that being a shock to the animals if it's done all in one shot.

I actually did that though this last week when I took out my rocks to scrub them down. I did a 100% change then but that's the only time I've ever done anything like that.

 

[2639]

<a href=showthread.php?s=&postid=8326991#post8326991 target=_blank>Originally posted</a> by Randall_James
100% water changes will not hurt a thing so long as you match salinity and temp... I change 100% per month myself but do it 25% a week. Just a lot easier to deal with and it allows me to blow out the rocks more often.

Waiting 30 days between wc's I think creates too large a swing in water quality, smaller more frequent in this case are less stressful IMO.

Is this an excessive amount of water changes? yea probably,

worth it?

Most certainly... I purchase no tank supplements, I purchase no test kits (hey with that much water changing, what could build up?) I have not now or ever had cyano, algae or any other issue to deal with that originates from excessive nutrient in the water column.

If you have the time and patience to do these changes, go for it...

Cost wise it is about a wash, test kits (good ones) are expensive as are other supplements. Test kits have a definite shelf life and they do no good if they are inaccurate. If you have a lot of calcium hungry stuff, Red Sea salt has a bit higher level of CA than say IO salt.

That's a very good point about the test kits going bad and the fact that you have no nutrients build up.

Do you protein skim or run carbon ? what levels do you keep your water? alk, ca, salinity etc?

 

[MCary]

These guys are right. Your not doing a 100% water change. Your doing a serial dilution. Plus by doing that many changes, basically a percentage of the water you are discarding everyday is the good water you just put in the day before.

Mike

 

[Randall_James]

Unless automated, daily changes are going to be overwhelming after a time. Weekly or 10 days should work great.

Without meaning to hijack this thread my levels stay pretty stable. I should mention that my topoff is 100% kalkwasser added only at night after the lights go out. This maintains CA/Alk levels. I maintained testing for around a year after going to this setup and finally ditched all the junk. Here are typical readings from back then:
Alk 2.7-2.9
CA 385-410 (I now use Reef Crystals instead of IO due to CA)
PH 8.1-8.4 (AM-PM)
Salinity 1.027
phosphates undetectable
Nitrites/nitrates Undetectable

I do keep carbon in the tank and this is just out of habit and I think it adsorbs any errors in my judgement

After almost a year of monitoring I finally just got tired of checking the levels. I do not advocate ignoring your levels but a long term stable tank is not going to change very quickly.

Any tank less than a year old should probably be monitored at least every other week.

I am just a big advocate of water changes. There are plenty of guys that get by on 10% every 3 or 4 weeks but I wonder what if any other issues they must deal with over a year.

I would love to see the actual water change schedule of the guys with algae, cyano, diatom,dino problems.

 

[2639]

That would be real nice to see actually. It's always good to compile data from all around to get a better idea of a better solution.

 

[Randall_James]

<a href=showthread.php?s=&postid=8327245#post8327245 target=_blank>Originally posted</a> by MCary
These guys are right. Your not doing a 100% water change. Your doing a serial dilution. Plus by doing that many changes, basically a percentage of the water you are discarding everyday is the good water you just put in the day before.

Mike

I calculated this out one day and if you did 30 water changes that equal 100% you are only loosing around 9% of your good water. This is really beginning to split hairs at any rate.

http://www.wetwebmedia.com/watchgantart.htm

Provides some good reading on water-changes. Anyway, I feel that a bit of overkill is better than going in the direction of inadequate...

 

[MCary]

Not to be splitting hairs. Just getting in technically correct. Randall, you also are not doing a 100% water change. You are doing a 25% change once a week. In order to do a 100% water change, you need to do it all at once. Lets look at it like this:

Your have 100 gallons of water A
You change 25% with Water B. Now you have 75 gal water A mixed with 25 gal of water B.
The next week you change 25% with water C. Now you have 25 gal water C, 56.25 gal water A, and 18.75 gal water B.

You will always have some percentage of water A. You will not have 100% of it out in a month. Technically speaking.

Mike

 

[jsdratm]

It would be more effective to take out large amounts of dirty water once a week rather than small amounts every day.

Lets say you have a 90 gallon tank and at the beginning of the month you have 90ppm nitrates and, for the sake of this exercise, nitrates in your tank don't increase. If you do a 3 gallon water change per day for 30 days, your nitrates level will be about 33.67ppm. If you do a 45 gallon water change every two weeks, your nitrates will be about 22.5ppm. If you do a 30 gallon water three times that month, your nitrates will be about 27ppm.

The math is pretty simple. Let's say your starting nitrate level is N and the decimal percentage value of the water change is P. Your nitrate level after a water change would be N1=N-(N*P). Then just replace N with N1 and keep iterating.

 

[imtheonlylp]

<a href=showthread.php?s=&postid=8327347#post8327347 target=_blank>Originally posted</a> by MCary

Your have 100 gallons of water A
You change 25% with Water B. Now you have 75 gal water A mixed with 25 gal of water B.
The next week you change 25% with water C. Now you have 25 gal water C, 56.25 gal water A, and 18.75 gal water B.

Mike

this is very true; hypothetically it seems possible, but scientifically and mathematically, it is impossible...almost like the baseball problem in the movie "Cooperstown"...the problem is as stated:

if a pitcher throws a baseball from the pitcher's mound to homeplate and halfway there it is measured to have travelled 30.25 ft...it still has 30.25 ft left to go...it is measured again at half of that, and has 15.125 ft left to travel before getting to homeplate...mathematically and theoretically, the ball would never get there...because that distance could always be divided...however, physically, we all know that it eventually crosses the plate though

i think the same applies in this water change case...you would never be doing a complete 100% water change...as someone stated before, as the days go on, the water that you are changing is more and more becoming the water that you have already added (new water)

 

[Randall_James]

It is possible to replace 100% of the water volume with no reduction in pollutants. And you do that about every 50 to 100 days.

You are confusing the subject here entirely with semantics of percentages. The benefits of the changes are not so much diminished as you might infer here. Yes you will remove more of the impurities with a few large changes over a number of smaller changes but not so much as you are implying here. This has been discussed into the ground. And without getting to far off the topic you can read R.H.Farleys article on this very subject.
http://reefkeeping.com/issues/2005-10/rhf/index.php#4

The fact that the tank is not suffering the more radical swings in water quality mean more to me than the total effect.

I would rather reduce the trash by 25% than 50 or 75% just for the sake of my livestock.

(to summarize the article, if you do a single 30G water change in a 100 gallon tank vs 30 one gallon changes, the difference in pollutant removal is only 5%. 25% vs 30%) And he is the chemist

 

[archie1709]

I do a 30 percent water change every 3 months with my reef tank...and i only have hang on the back filtration and powerheads....so I guess I am out of the discussion here.

 

[Randall_James]

<a href=showthread.php?s=&postid=8330410#post8330410 target=_blank>Originally posted</a> by archie1709
I do a 30 percent water change every 3 months with my reef tank...and i only have hang on the back filtration and powerheads....so I guess I am out of the discussion here.

There are guys that never do water changes