50% water change

[hle_81]

i change 50% of the water in my tank every week. is that too much?

[Slappy*McFish]

nah...not at all:D

[catjo]

That's what I do.....no problems here!

[Bantam]

the only prob would be if the water conditions; pH & temp were altered significantly. other than that i imagine you have very happy fish

[thom336]

water changes to be done to suit your tank and fishes needs...if 50% a week works for you, then carry on. If you feel it is too much, then cut it down....there are advantages to cutting it down. As mentioned, temp, pH and hardness would be more stable, you wouldnt have to carry so much water around, the tank would get disturbed less....but i dont see any major problems with 50% a week, if you feel it is right.

if it would help, i'll let you know that i change 25% a month on my tank...some people would say that is far too little, but its what works for me and my fish. All the fish are healthy, water is crystal clear, water tests all com out good, excellent in fact. So its really what each individual tank needs.

Hope this helps.

[RTR]

And then breeders change 100-200% per day. There are few disadvantages to changing water, many advantages.

[redsilver]

50% per week is fine...:)

[thom336]

RTR, at this point may i b bold enough to ask you to state these advantages?

[Tiger15]

It's a problem only if you amend the water with chemicals. A large water change in amended water can lead to large chemistry swing. If you do large water change routinely with no amendment, your water chemistry will approach that of your tap water.

[RTR]

Advantages include 1)the fact that your tank water approaches your tap water parameters excepting any pollutants developed since the last change - so in effect the more changes you do, the more and larger percentage changes you can do. 2) The water in the tank more closely approximates natural conditions (not native parameters, different thing) in that pollutants and waste do not linger in the area but are flushed out. 3) fresh water without pheromones and hormones and waste stimulates appetite and breeding. 4) in low KH water, nitrification destruction of buffering is not an issue. In higher KH water, downward pH drift is avoided. 5) in planted tanks, micronutrients are replenished. 6) Overall, the more frequently you partial and the larger volumes you do per partial, the more stable the tank water conditions will be.

Disadvantages are 1) that you have to do it. 2) If you are doing water modifications, you have to prepare more pre-modified water. 3) If you are doing infrequent changes, you cannot do large volumes due to possible differences in source and tank water.

HTH

[thom336]

i fully agree. but i would like to point out that stable water quality not only comes from water changes, but also from light stocking, good planting and good filtration.

however good water changes are, however, i believe it does more bad than good to do over 50% a week (50% a week still fine ;) ), unless of course you are raising young fry which do need prestine water conditions.

[125gJoe]

I think most know this, but then again some may not, and it's worth repeating, and repeating.... :)

It's important to keep your water changes very close to the same temperatures --- tank water and 'new' water....

[RTR]

thom - I'm not trying to be argumentative, I'd really like to know as this topic comes up so often - Why do feel that frequent larger-scale changes (>50% per week) does more harm than good? I don't understand? What is the downside you see?

I don't do changes at that level (other than fry) myself as I have too many tanks to tend, but I don't see any downside.

[JazzUp]

Uhh... when I do water changes, I can't help myself but change at least 80%. Yes, you can tell the fish really enjoy the new fresh water!

[StevieM]

With regards to changing out water and maintaining constant temperature with the replacement water and tank water....I thought I have heard of people adding water of a slightly lower temperature which supposedly aids in triggering spawning. Just a thought, but I could've sworn I've read about that in numerous publications claiming that it "simulates natural post-rainfall " conditions. I don't have much experience with breeding fish, other than some livebearers, but I just thought I would throw that out there....

steve

[thom336]

i can see where you are coming from - but i can also see that you can have 'overly clean' conditions. It is being suggested by many experts that dirt in the gut actually helps aid a fishes digestion - but if you are changing more than 50% of the water per week (with the exeption of course of the discus fish, another topic completely) then this dirt required doesnt have time to accumilate. Also plants would benefit from less frequent water changes - dont get me wrong, i am in NO way suggesting against water changes - they are VITAL. but i do believe you can over do it.

[thom336]

sorry stevie, i skipped over your post there in answering RTR. it can help to trigger spawning by carrying out large water changes, and in certain cases with cooler water - but never more than afew degrees cooler than that of the aquarium. It can also be beneficial to fish in the summer months to recieve a 'cool shower', but again never more than afew degrees cooler.

[StevieM]

that's pretty much what I figured....just wanted to make sure that I was on track. thanks for the input.

steve

[RTR]

Perhaps we need a definition of "dirt" - do you mean soil? If so, does this mean those of us with soilless tanks are killing their fish? Should we be adding soil to out tanks? How much and how often?

Organic waste in the tank is not "dirt" by any scientific definition I know. And fish do not normally eat such so how does it get into their gut?

I'm afraid this sounds like a myth in the making to me.

[Luca Brazzi]

Wouldnt doing water changes too frequently/too large over time tend to reduce/destroy the bacteria colony? For example, if you had an established biological filter that was balanced to support the daily ammonia generated by your fish load, but you were constantly changing large amounts of the water, the bacteria would never get fed (or get fed much less ammo than needed) hence it would starve. Then if you stopped doing the massive/frequent changes you would get an ammonia and possibly nitrite spike.

[thom336]

luca i love u! well, not literally...but u hav given new life 2 my opinion, and in fact i was think of summin along those lines for a long time. (yea right....lol). but luca is right, the bacteria colony in your filter does need feeding.

RTR - i assue you what i say is based on facts and evidence. just i cannot find it at the moment. im not entirely sure what is meant by 'dirt' myself, i just act like i do. smile and nod...gets you everywhere. but i can see where your coming from, i didnt believe it myself at first, but i was convinced. i hav a magazine article on it...and i shall try and find it and quote from it on here when i do.

[jiggerpolebill]

RTR - if you or anybody else are expecting any of this to be backed up with any scientific references, you can forget about it. his beliefs are all he needs for evidence and they should be enough for you as well.

[RTR]

No, because ammonia production and release is a fairly steady function in tanks, and is oxidized fairly quickly. It is spread throughout the 24 hour day, so unless you have constant flow through (an open system rather than a closed system) you would only be reducing the titer of ammonia for a very brief period which have no measureable effect on the colony. You are depleting the stable end products because they are stable, not transitory as are ammonia and nitrites.

jpb: I am unfortunately all too well aware of that, but I cannot allow pseudo-science and mythology to go unchallenged - the less-experienced members might actually believe some of this imagination to be real.

[Luca Brazzi]

so unless you have constant flow through (an open system rather than a closed system)

So then you can change the water too much... Thanks for the info RTR!

I guess if you were continually changing the water though, you wouldnt need a bio-filter at all.

As to the original post about changing 50% / week, hope youve got a python, or a real tiny tank. Ive got a betta in a filterless 2 gal that I made, and I change bout 90% of that every other week.

However, the real answer to the original post cannot be answered accurately without further information as to what the whole picture is (inhabitants, water parameters, other dynamics, etc.). Without more detailed info, all you will get for an answer is the pure speculation youve received thus far which is based on tanks that are not yours.

Luca...

[Clownloach458]

heck yeah,lol, its ok. dude you have like super clean water, thats good, i try to do 25% water change weekly

[RTR]

I did not say that you can change the water too much - you have gotten your chain jerked before for putting words in people's mouths. Your level of rewsponse in pathetic. Insulting but pathetic.

A flow-through or open system does not use filters, mechanical or biological, although chemical are commonly employed upstream of the tank. They require no filters as they emulate stream or reef conditions of constant high-volume water movement and pass-through. These are not home systems under conventional hobby situations.

In closed sytems, as in normally the case for the hobbyist or even the commercial tank breeder, high percentage changes are entirely beneficial.

[goldfish freak]

RTR, I find it funny that some people think that they know it all, and are arrogant about their supposed "wisdom".

[jiggerpolebill]

i change 50% of the water in my tank every week. is that too much?

this post can be answered. im new to fish keeping as well, and one of the best purchases ive made is 'The Simple Guide to Freshwater Aquariums, by David E. Boruchowitz'. Mr Boruchowitz is a very big advocate of water changes. here are a couple of exerpts from this book:

"It would be wonderful, however, if you could manage an even greater rate of change, say half of the water each week; then 75 percent of the water in your tank would be two weeks old or less, and close to 90 percent will always have been added in the last three weeks. Your fish will truly thrive on such a regimen."
Chapter 13, page 157

"No amount of filtration can make up for a deficiency in water changes, but water changes can make up for deficiencies in filtration. If you change water often enough you wont need any filtration at all. Yet even I - water-changing fanatic that I am - recognize that such systems are practical for maybe only one hobbyist out of a thousand, and almost never for the beginning hobbyists. Too bad."
Chapter 13, page 156

on flow-through systems... "Such a setup is typically found in commercial operations, but it is often used in a modified form as a drip overflow system by home aquarists with several tanks. The only difference here is that the water flows through the system at a much slower rate. Instead of making up for a filtration system, it serves as an automatic water-changing system. Each aquarium still has a filter, but the water is kept fresh without periodic changes."
Chapter 7, page 106

David E. Boruchowitz is the editor of Tropical Fish Hobbyist magazine and has a few other books under his belt as well. here is a link to some of his other books:

http://www.amazon.com/exec/obidos/search-handle-url/index=books&field-author=Boruchowitz%2C%20David%20E./103-1153900-1720618

ive looked through this book again, but cannot find anywhere where it says that you can change your water too much. i'll continue to look, and if i find anything concerning this, i'll post it.

you'll notice at the top of the list is a book written with Dr. Herbert Axelrod. i think this says alot about him and his recommendations. i'll go out on a limb and say that Boruchowitz knows as much as or more about fishkeeping than anybody on this board. i highly recommend this book. its very easy to read and reasonably priced as well.

id also check around the internet and maybe post this same question on some other forums.

[thom336]

"RTR, I find it funny that some people think that they know it all, and are arrogant about their supposed "wisdom"."
if thats me ur referring to, then you got it wrong. i dont think i know it all, and admit i have alot to learn still, like we all do. i have also agreed with both sides of this topic right the way through;

"i fully agree."
"i can see where you are coming from"
"but i can see where your coming from"
- all posted by me. im just saying here that you've got me wrong on this one, and im sorry about that.

water changes are vital, but what im saying is not to go over the top. it is possible to be too clean...and im just letting people know. maybe some of you need to re-read my posts here.

[beviking]

Originally posted by jiggerpolebill
i'll go out on a limb and say that Boruchowitz knows more about fishkeeping than anybody on this board. \

Not saying you're wrong jpb, but "going out on a limb" is what you're doing with a statement like that I.M.O..

RTR - I would ask for a raise, that is, if you get paid for doing this. If not, ask for a scotch!;)

[ROLLIN]

On my tanks 10 gallons and up I change about 40 - 50% a week with no problems. On my 2 gallon tank with a betta I change about 240% a week with no problems either.

[goldfish freak]

Thom336, I was not referring to you.

[Luca Brazzi]

Does your betta tank have a filter? Mine doesnt. Its amazing how much ammo bettas can tolerate. Theyd be a great fish to used for a fishy cycle if you put some dividers in the tank. I still change his water quite often though, 90% every 2 weeks.

[thom336]

oops, sorry goldfish freak, but i just get so used to it.
jiggerpolebill was thou....ah well...

[ROLLIN]

Originally posted by Luca Brazzi
Does your betta tank have a filter? Mine doesnt. Its amazing how much ammo bettas can tolerate. Theyd be a great fish to used for a fishy cycle if you put some dividers in the tank. I still change his water quite often though, 90% every 2 weeks.



No, mine doesnt either. Bettas might be able to tolerate ammonia, but Id rather mine not. Doing a water change on a tank that small only takes about a minute, if that.

[jiggerpolebill]

beviking - yeah, that was the gest of it. by going out on a limb, it was my opinion. ill place a small edit there. he may not be THE final authority on the hobby, but he certainly knows a thing or two, and has been around in it for almost 50 years.

i posted that for the original question(hle 81), so that they could get some rather trustworthy(i think) advice from a reputable source. thom, what part of what post doest thou think was bestowed on thou?

[thom336]

Originally posted by jiggerpolebill
RTR - if you or anybody else are expecting any of this to be backed up with any scientific references, you can forget about it. his beliefs are all he needs for evidence and they should be enough for you as well.

sorry...did i interpret this wrongly?

[beviking]

That's how I interpreted it.

jpb - "he may not be THE final authority on the hobby...". Then again he may. That is if there is an absolute amount of information on this (or any) subject. Does any1 know EVERYTHING about any particular thing (I know I'm being a bit hypothetical here)?
Point is, that's what discussion is for. State what we know and back it up with credible sources if need be.
I certainly agree with your advice and don't doubt it's credibility either. I'm inclined to agree with your first post as well, but that is only based on 1 thread.

[jiggerpolebill]

interpreted correctly.

as in another thread where an idea or belief is laid out to be so, without any attempt to back it up or make any proof to substantiate its claim. "its simply is that way, because that's what i think." instead of, "i think its this way because so-and-so states in this document that it is because......" or "it is this way because its been proven/scientifically known to yada yada yada..."

[thom336]

i tend to base my fishkeeping on experiance and knowledge....i would much rather watch my aquarium grow and develop than have my head stuck in a document. you can learn more from your fish than you can from any science literiture. i have never forced what i have said onto anyone, or said that what i say i right - i simply put my view across.

[OrionGirl]

Luca and thom--Nice that you're joining forces. Consider this a warning. If you can not play politely with others, and accept that your opinions are not going to be accepted without question, we will take measures you may not like.

Closing this thread.