Really, how often do you need to change water?

[WarDaddy]

I most my reading about freshwater tanks, changes every two weeks is frequent, and once a month of 20-30 percent is normal. Here I am seeing water changes daily, of 30-50 percent. Is that true?

I tell you what, the fish are beautiful, but 30-50% a day is not the kind of aquarium that I had in mind for my son to learn about animal, fish and other such things that kids learn from keeping pets.

Thanks,
Bryan

[Webzilla]

Everyone has their techniques that's for sure. Personally I change 30-40% Max a week in my tank, but then again it is 175 gallons. Smaller tanks = more water change IMO. Also filteration has a whole lot to do with WC schedules IMO. The fish are beautiful, there is no other freshwater fish like discus. I love them, it's almost like they have personality - heck they do have personality I'm sure of it. One thing, if you can keep Discus you can keep anything freshwater. They are not that hard IMO they just require attention to details and consitantacy "Whatever that is"! :) - A great traite for one to learn growing up thats for sure.

I'm out!

John....

[Anonapersona]

It is a lot like growing orchids.

You wouldn't buy a live orchid for him would you?

[steve s]

Hi Dad,
keeping fish is fun, spending that half hour every night or even
every other night, no TV, homework chores,just one on
one. Both learning and sharing. Priceless.

[Howie_W]

I most my reading about freshwater tanks, changes every two weeks is frequent, and once a month of 20-30 percent is normal. Here I am seeing water changes daily, of 30-50 percent. Is that true?



I change closer to 80% daily. Discus are not for everyone. :)


Howie

[Ardan]

I think 50%'day is best. this is from my person experiences as the discus grow bigger and are healthier and better colors.
It does depend on how much and how often you feed and how clean you keep the tank.
it is a bit of work but their are ways to make it easier (pumps and hoses)

It does become addictive to change water too! I think its good therapy to play in the water ;D

[babyjess210]

I change 80% water daily and sometimes twice a day on the weekend with my 2 year old daughter. It's actually fun to see her helping with the feeding , water change, cleaning the tank and feeding again. Once you get your water change "system" in order, it will only take about 15-25 minute a day.

[WarDaddy]

It is a lot like growing orchids.

You wouldn't buy a live orchid for him would you?


Hey, I can grow orchids! I have several dendrobs that bloom for me once or twice a year for 7 years now. Cinbidiums that bloom every year and a Phal that grows, yet to bloom:-)

If orchids are a harbinger of fish keeping skills, I should do ok.

:P

[Wolf_Mek]

I most my reading about freshwater tanks, changes every two weeks is frequent, and once a month of 20-30 percent is normal.

Unfortunately, this information is inccacurate at best. 20-30% per week is the minimum on most FW tanks... many people do that 2X a week on their FW tanks.

[Anonapersona]

Hey, I can grow orchids! I have several dendrobs that bloom for me once or twice a year for 7 years now. Cinbidiums that bloom every year and a Phal that grows, yet to bloom:-)

If orchids are a harbinger of fish keeping skills, I should do ok.

:P


That is a good indicator, IMO.

Orchids require steady tending, no sudden changes, a good eye for developing problems, an understanding of when special measures are called for. After you've had some success, you can bend the rules without disaster, but at the start you follow a proven recipe.

With discus, that proven recipe is changing water daily. The number of fish per gallon will directly impact how much you ought to change, but starting with 50% a day and something like 1 fish per 10 gallons is a good place to begin. Adjust for smaller fish, excellent filtration, acidic water, excellent cleanliness.

[ShinShin]

I'm glad to see everybody is doing big water changes daily :). I do 40% minimum daily, usually more.

[Barb Newell]

I do about 60% daily on adults, 160% daily on fry.

Barb :)

[Dave C]

"I'm glad to see everybody is doing big water changes daily."

That strikes me as a really odd comment. I know what you mean, that you believe that because everyone (that responded) is doing daily w/c they will have success and their Discus will not suffer. But wouldn't it make you happier if there were people having success with weekly w/c? Wouldn't that mean that there is hope for everyone to have similar success?

I can't believe that if WarDaddy were to get a 100g tank and stock it with 6 adult Discus that daily w/c would be required. I'm sure there would still be people that would do it daily but it sure wouldn't be a requirement of the fish. There would be no need to hit adults with tons of food, just a couple feedings of clean food (i.e. bloodworms) each day and the mess would be minimal. I'd be tempted to try it doing a weekly w/c.

What makes me glad is that for over a year now I've kept an average of 200 Discus in stock in tanks totalling about 500g and had good success with three 50% w/c a week and simple tank bottom siphons the other days. It makes me glad that my water consumption is about 1/2 of what it used to be. And it makes me ecstatic that my fish have not suffered as a result of this lowered w/c frequency. I see that as progress in my pursuit of this hobby. That doesn't mean that everyone should copy my methods. It just means that success with Discus can be had without doing daily 80% w/c... something I wouldn't have believe a couple of years ago.

[Webzilla]

Daily 50% or more water changes on multiple tanks? That is a nightmare unless one has it automated somehow. We all have our methods that work for us. My 30-40% weekly "Friday after work" works for me. Then again I don't breed or raise fry I just enjoy the scenery.

[Anonapersona]

What makes me glad is that for over a year now I've kept an average of 200 Discus in stock in tanks totalling about 500g and had good success with three 50% w/c a week and simple tank bottom siphons the other days.

Dave,

What is the filtration you use, and the pH of your water? And how big are the fish?

200 discus in 500g 50% WC every other day is a ratio of 1.6 fish-days/gallon, assuming you included the water in any sumps. I'm still collecting data points on my theory in progress, so the outlying numbers are of great interest. With young fish that is reasonable, with adults, I'd expect there to be awesome filtration and acidic water.

I recall the Dkarc said he had 1.5" fry with a ratio of 5.5 (100 fry, 30g, 2x30% daily) with a large wet/dry, daily wiping, no leftover food, cleaning the prefilter daily.

I'd like to include an adjustment to the ratio for the size of the fish or better the amount of food put into the tank, but I can't quite see how to do that. Still thinkin'.

[Dave C]

I have some tanks that are filtered with a wet/dry & sponge, some just sponge, but all tanks also have a Magnum HOT filter with micron filter for mechanical filtration running 24/7. I keep about 50 1-2.5" fish in a 55g tank... about 30 2.5"-4" fish in the same tank and 20 4-6" fish in the same tank. My water has a pH of 7.5. I'm less concerned about the crowding with adults as I feed them less food less often and the tank is a couple of degrees cooler. I find that 3-4" fish eat the most food by volume (as opposed to food compared to body size) so I'm most aware of tank cleanliness at that size.

[Anonapersona]

I have some tanks that are filtered with a wet/dry & sponge, some just sponge, but all tanks also have a Magnum HOT filter with micron filter for mechanical filtration running 24/7. I keep about 50 1-2.5" fish in a 55g tank... about 30 2.5"-4" fish in the same tank and 20 4-6" fish in the same tank. My water has a pH of 7.5. I'm less concerned about the crowding with adults as I feed them less food less often and the tank is a couple of degrees cooler. I find that 3-4" fish eat the most food by volume (as opposed to food compared to body size) so I'm most aware of tank cleanliness at that size.


Thanks, this helps clarify what works.
50@1"-2.5", 55g (no W/D assumed), 50% each 2 days = 3.6 fish-days/gallon
30@2.5"-4", 55g +10g Wet/dry sump assumed, 50%x2days = 1.8 fish-days/gallon
20@4"-6", 55g+10g in wet/dry assumed, 50%x2days = 1.2 fish-days/gallon
(please allow me to correct any bad assumptions here)

Now, it looks like the key here is that you are running double or triple filtration with the wet/dry, sponge, and HOT. I've already seen that a wet/dry is approximately equal to a planted tank in that it allows a near doubling of fish-days/gallon over a sponge filter (ignoring a lot of other factors). Looking at the adults, it appears that the HOT may double it again, or that might be the lower temp/lower feeding. It might be that each type of filtration adds 0.3 fish-days/g to the mix, as a wet/dry typically has a prefilter so is like a double.

Hey, thanks for indulging me on this. One day I may actually get it to work well!

Makes me wonder if Wolf has ever let the tank go long enough to see any discomfort in the fish -- he once said he did 95% water changes, ran 2 AC500s, a HOT and 2 sponges for 7 adults!

[Dave C]

I agree. The add'l mechanical filtration that comes from the w/d or the Magnum allows me to change less water. For me it proves that point that clean water is as good as "new" water. If your nitrates are <=5ms and your tank bottom is clean and your water is clear I don't know why you're changing more water. It can't hurt but it's unnecessary in my opinion.

[JeffreyRichard]

MY EXPERIENCE ...

I have been able to keep healthy discus doing two 50% water changes weekly. These fish are kept in a low bioload environment with no special filtration (I use air-driven sponges mostly). A low bioload would be light number of fish relative to the gallons in the tank, with no more than two feedings daily.

Factors that would influence the frequency of water changes -
- number of fish ... if you are try to grow out 25 fish in a 55 gallon tank, you'll need to do LOTs of water changes
- if you are try to grow fish fast through frequent feeding, you'll need to do lot's of water change
- you'll need to do more changes if you are trying to breed a pair

One will achieve VERY good success IMO doing daily water changes. However, daily water changes are NOT NECESSARY to be successful.

Correction made today ... thanks Dave

[JeffreyRichard]

I change closer to 80% daily. Discus are not for everyone. :)


Howie


Your approach works for you and is certainly a successful approach for many ... however, to imply that EVERYONE must dedicate this level of dedication is inaccurate. I successfully keep discus with much less work ... see above.

[RyanH]

Hey guys,

I thought I would wade in with my two cents:

I have in a 75 gallon tank with 8 older juveniles/young adults. They are about 4" long. I run 5 hydro V's (3 on a low airflow for biological filtration and 2 cranked way up for mechanical) in the tank and an A/C 500 with a filtermax III prefilter and sponge media running on it. It is barebottom. I change 80% of their water 2-3 times per week. They are fed CBW's, Hikari bloodworms, Ocean Nutrition formula 1 & 2, and Tetrabits. They are growing so fast that I can almost sit and watch them get bigger. I got them when they were around 2". I changed 50-75% of their water almost daily up until they were about 3-3 1/2". When they grow to a size that I am happy with I will decrease their water changes to 2-3 times per week at about 40%.... the same as my other adults. I will also then consider putting them into a showtank.

I've used this system for some time now and it has worked very well for me. Some people change more, some change less. Some insist on substrate right away and some are able to show patience. I like to see new people really taking their time and erring on the side of caution while they are just starting out with Discus. Once they have grown out their fish and they know what they are doing, they should be encouraged to experiment with different methods so they can find methods that work for them. As you all have said, and I agree, there are many ways to successfully keep Discus. But a conservative approach is logical and makes sense if it is given even a small amount of consideration.

Jeff, as you can see, I am not a water change Nazi. :) Even though we've had our disagreements, I believe that you and I see eye to eye on most things concerning how to properly care for Discus.

There have been some pretty heated discussions and even some personal attacks here in the past few days that I would really like to see toned down. This is a place where new people are coming into our hobby and are looking for answers to their questions. They deserve to have a place where they can learn and interact and not feel uncomfortable or afraid to post for fear that it will start an argument. Let's play nice and make a good impression.

-Ryan

[Anonapersona]

Well, this is exactly why I am trying to reconcile these two approaches with my fish-day/gallon calculation, because both of your positions are true at the same time.

And I want to know how to know how many fish is too many, how much filtration is enough, and how many water changes are required.... within some reasonable range, of course.

You see, where I'm trying to go on this is... if I leave town and someone feeds my fish and siphons the tank and I have a lot of filtration, but not so much the fish can't sleep at night, can they go with no water changes for 5 to 10 days? I don't want to come home to find little fungusy spots on the fins and little graves in the garden. If it is not possible to go 5 days without a water change, then I can move all the fish around to different tanks and try to get this wet/dry started and stable in the next 9 days, but that is a very tall order.

If it is true that more filtration is as good as new water, up to a point, of course, then I may be able to squeek by if Gene comes to change water for me once, I hate to ask him to come twice, it is a long way!

hmmm, 22 fish now, 5 days to WC, 70% WC, 55 gallons = 2.8 that's too high for 3" fish.

If Grandma can siphon out and replace 4 gallons a day that is a .08 WC, that ratio is 5, then a 70% WC makes it -- blah-- gotta do a spread sheet.

[RyanH]

I've gone away MANY times for 5-7 days and my fish had no water changes at all. They were fine.

My wife and I spent two weeks in Italy this spring I had a friend come in twice and check on them for me. They were fine.

I cleaned the tanks before I left and basically changed all the water. I set an auto feeder to give them a very small amount of food every day. When I got back my fish were hungry but healthy. It can be done.

hth!
-Ryan

[Anonapersona]

Hey guys,

I thought I would wade in with my two cents:

I have in a 75 gallon tank with 8 older juveniles/young adults. They are about 4" long. I run 5 hydro V's (3 on a low airflow for biological filtration and 2 cranked way up for mechanical) in the tank and an A/C 500 with a filtermax III prefilter and sponge media running on it. It is barebottom. I change 80% of their water 2-3 times per week. -Ryan


That is a ratio of 0.4, using 3 days to water changes, which still puts you into the perfectionist category Ryan! With so much filtration I was expecting that that number might be higher for not full grown fish.

[RyanH]

LOL... the main reason for the 5 sponge filters is so I have a couple of extras ready to go for other tanks as my fish grow and I feel that I want to move them around. Maybe I am a perfectionist though. ;D

[Anonapersona]

I've gone away MANY times for 5-7 days and my fish had no water changes at all. They were fine.

OK, starting at 0.4 ratio and 75 gallons your tank has a steady state fish waste equal to 30 fish-days.

If you change all the water you start at zero fish waste and in 7 days 8 fish have made 56 fish-days of waste. Almost twice as dirty as you normally let it get but with half the daily food that's probably equal to normal. The fish probably never noticed any difference in the water, only the food.

OK, well all these mental gymnastics have helped a lot.

First, the concept of the near 100% water change to begin with. That buys a lot of time. Then half-rations. That doubles the time to the next water change.

So, for my tank, with 22 young fish the normal ratio is between 0.6 and 0.8 with 50% to 70% water changes. Starting with all fresh water or nearly so, in 4 days we have 88 fish-days of waste or twice the normal level -- but if they only get half the normal food, this would be OK.

Meanwhile I'll add the HOT with a normal filter and biomedia inside and add biomedia to the back of the Penguin and add the huge sponge that Gene gave me.... and I'll start measuring nitrate daily to see how it varies with normal water changes.

That sounds like a plan. Thanks for the input.

[RyanH]

No problem... and just to let you know:

The amount of food that was given to my fish was more like 20% of what they would normally get. For trips that were 5 days or less, I wouldn't bother feeding them at all.

hth!!
-Ryan

[Howie_W]

There have been some pretty heated discussions and even some personal attacks here in the past few days that I would really like to see toned down. This is a place where new people are coming into our hobby and are looking for answers to their questions. They deserve to have a place where they can learn and interact and not feel uncomfortable or afraid to post for fear that it will start an argument. Let's play nice and make a good impression.

-Ryan



I'd like to say thank you to Ryan for pointing this out. In truth what can be viewed as a personal attack I see as plain old fashioned rudeness...and completely unnecessary.

Going back to the orginal poster of this thread, the inquiry was in regards to wanting to know if there were people who actually performed large water changes. I've been in this hobby for quite a while, and have had plenty of time to experiment with both large and small water changes...all of which work and serve their purpose under varying circumstances. I also enjoy discussing different methods of fish keeping, and never tell people that only one method is the one to use.

As Ryan pointed out, caution is indeed the better part of valor for novices, and a good place to start. In the end, everyone makes their own decisions, and the more information there is to work with, the better off we all are.

Howie

[Webzilla]

Anonapersona,

I read a lot of your post! :D Your quite an Einstein or at least heading down that road. By time you figure all your equational math out you'll have an all time best seller on your hands. ;D , I know one thing your fish will be thriving from a lot of love and there is not doubt in my mind you are going to be one of the best water consultants around when you finally get the fish ration - feeding - water change equation down. When your new book comes out - Can I get a signed copy? :D Any how I like your posts, they are fun to read, brain twisters at times but mostly quite enjoyable.

I'm out!

John......

[JeffreyRichard]

Jeff, as you can see, I am not a water change Nazi. :) Even though we've had our disagreements, I believe that you and I see eye to eye on most things concerning how to properly care for Discus.

There have been some pretty heated discussions and even some personal attacks here in the past few days that I would really like to see toned down. This is a place where new people are coming into our hobby and are looking for answers to their questions. They deserve to have a place where they can learn and interact and not feel uncomfortable or afraid to post for fear that it will start an argument. Let's play nice and make a good impression.

-Ryan


Yes I have contributed to this ...

I'm not against water changes ...

My concern is exactly what the WarDaddy asked to start the thread ... are massive water changes necessary? In some cases, yes; but in many others, especially where someone just wants to keep a reasonable number of discus in a reasonable size tank, the answer is NO.

I just don't want to see someone scared off by extreme hasbandry techniques ...

I advoce presenting a prefered method as an ALTERNATIVE ... with references to other alternatives. That to me presents a fairer more balanced opinion.

Just some thoughts ...

[Anonapersona]

Well, hey, I'm lovin' this!

I think it is really useful for successful discus keepers to tell us novices how they do it. Particularly when they come at the issues from different perspectives.

I (and probably most of us novices who are decent fishkeepers but new to discus) do not expect there to be ONE RIGHT WAY. Rather I expect there will be guiding principles around which one can choose various paths to follow.

It does take a long time to get used to the idea of even twice weekly water changes, really, coming from simple tropical or African tanks. Heck the hi-tech planted tanks were seen as unusual with 50% weekly water changes.

It -is- enough to scare anyone off. You guys need to remember that there are very many people who think a monthly water change ought to be enough for a fish -- they live in muddy streams for goodness sake. So, just realize, you both (both the daily water change group and the 2x/week group) seem like nuts to "outsiders" ! Shoot, even the saltwater people seem to spend their time and money trying to -not- change any water at all.

It is really important that people see there are several ways that work. Why they work is important to understand.

[Webzilla]

Anonapersona,


Yes! I would agree with that 100%.