What's the pupose of a water change in a planted tank - The Planted Tank Forum
 
LinkBack Thread Tools Display Modes
post #1 of 13 (permalink) Old 11-06-2007, 07:51 PM Thread Starter
Algae Grower
 
PTrader: (1/100%)
Join Date: Sep 2007
Location: Roanoke, VA
Posts: 67
What's the pupose of a water change in a planted tank

I've been keeping non-planted fw tanks and sw reef tanks for 20+ years and have done water changes religiously on all of them. The primary reason for doing water changes on these aquariums is to get rid of unwanted nitrates and/or phosphates.

I am now doing my first planted tank where nitrates and phosphates are beneficial. So why do water changes? What do they take out or add to the tank? Trace elements?
fourtanks is offline  
Sponsored Links
Advertisement
 
post #2 of 13 (permalink) Old 11-06-2007, 08:09 PM
Planted Tank Guru
 
tazcrash69's Avatar
 
PTrader: (22/100%)
Join Date: Sep 2005
Location: Hawthorne, NJ
Posts: 3,207
IMO It depends on the tank.
I have a low-tech low light tank where I do infrequent water changes to replace Ca & Mg with my liquid rock.
When I dosed EI (Estimative Index: where all the plant nutrients are dosed to excess so nothing is missing, and you perform 50% water changes weekly) on my high tech tank, it is basically to reset the nutrient levels.

Walter

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
and
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
or my
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.
Proud former member of:

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


--May the floor under your tank always be dry, and your glass clear!!!

Last edited by tazcrash69; 11-06-2007 at 08:37 PM. Reason: removed extra word
tazcrash69 is offline  
post #3 of 13 (permalink) Old 11-06-2007, 08:35 PM
Planted Member
 
aquaman3000's Avatar
 
PTrader: (3/100%)
Join Date: Oct 2006
Location: Atlantis
Posts: 171
Water changes are used extensively with Tom Barr's Estimative Index dosing method to "reset" the aquarium nutrients.

Water changes are still useful with other dosing schemes to help replace some traces and minerals like tazcrash69 mentioned, but I think there are also a number of things that can be removed that aren't really measureable like urea, allelopathy chemicals, tannic acid discoloration, etc. I know that fish and plants seem to react positively whenever I perform a water change.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
aquaman3000 is offline  
 
post #4 of 13 (permalink) Old 11-06-2007, 08:46 PM
Planted Tank Enthusiast
 
Madfish's Avatar
 
PTrader: (11/100%)
Join Date: Sep 2007
Location: WA
Posts: 789
Send a message via MSN to Madfish Send a message via Yahoo to Madfish
But then you have low-tech tanks where some people dont even do a water change but only once a year. But that is something you would have to look into on the low tech page Im a high tech kind of guy here.

Whats this green fuzzy stuff thats growing in my tank.
Madfish is offline  
post #5 of 13 (permalink) Old 11-06-2007, 09:03 PM
Planted Tank Enthusiast
 
Mangala's Avatar
 
PTrader: (1/100%)
Join Date: Jul 2006
Location: Seattle, WA
Posts: 562
Yes - Mostly, I've found that if I have breeding fish, they very very much prefer a water change at least once a week, no matter how many plants I have in there, because I overfeed to let the babies munch on as much food as possible. I actually have pretty thick green water in the breeding tank most of the time, and water changes let me see how big the babies have gotten since the week prior.

However, in my biggest tank, I have far too many fish so I need to change the water once every two weeks or so.

In my lowest stocked tank, I rarely change the water.

really, you have to have enough space for the fish you have to move around, and enough plants to soak up the nutrients that the fish are secreting. If you are out of balance that way, you can't get by doing no water changes.
Mangala is offline  
post #6 of 13 (permalink) Old 11-06-2007, 10:19 PM
Planted Tank Guru
 
plantbrain's Avatar
 
PTrader: (267/100%)
Join Date: Dec 2003
Location: The swamp
Posts: 13,609
Quote:
Originally Posted by aquaman3000 View Post
Water changes are used extensively with Tom Barr's Estimative Index dosing method to "reset" the aquarium nutrients.
Amano seems to have been using large weekly water changes for the last 35 years as well. Jeff Senske, CAU, David Oliver, many of the top scapers in the world, all seem to have this habit. I certainly did not invent it, I just use them like everyone else.

In a well monitored reef set up correctly, some export vuia macro algae remove most of these and you can get away without water changes for very long periods, this is due mostly to the cost of Salt for water changes.

In non CO2 planted tanks, the balance seeks to match the fish waste with the plant uptake and growth. So you need to have a good balance between fish load/feeding/waste and plant demands.

But this process can go on very well for several years without water changes.
Still, it is generally better to error on the less side with fish waste etc, and top off with a little ferts here and there. Bacter decompose most of the waste and plants take it up and sequester it, just like in refugiums for marine systems for export as trimmings.

So it's just using biological organisms to do the work instead of water changes.

Like agriculture, when we add CO2 gas and try to grow things much faster(10-24X faster), with have to add fertilizers.


Regards,
Tom Barr




Regards,
Tom Barr
plantbrain is offline  
post #7 of 13 (permalink) Old 11-07-2007, 05:54 PM
Planted Tank Guru
 
Robert H's Avatar
 
PTrader: (31/100%)
Join Date: Apr 2003
Location: Salem Oregon
Posts: 2,328
Regular water changes have been part of good aquarium care for decades. It was usually done for the health of the fish more than the plants. Freshwater is high in oxygen and low in DOC. What Tom invented was specifically useing water changes as part of a fertilization system to cancell out build up of exces nutrients from adding nutrients on a daily basis. While Tom did not invent "water changing" his reason fo doing it is more unique, and advocating 50% or higher water changes every week is FAR from the norm. Some would call extreme.

Long before Tom came up with EI, I was taught back in the 80s to do 20 to 30% water changes every two weeks, maybe once a week if you didn't mind the work. This was to help keep the water CLEAN. To keep dissolved organic compounds low, not to flush out nutrients that YOU were adding on a daily basis.

Robert Paul Hudson

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Kindness like love is unconditional
Robert H is offline  
post #8 of 13 (permalink) Old 11-07-2007, 06:21 PM
 
PTrader: (2/100%)
Join Date: Aug 2007
Posts: 97
I just have to figure that, while the plants make use of nitrate, phosphate, and other organic products, there has to be a big part of the waste that just builds up and must be removed in our closed systems. Same thing happens in reef tanks; macroalgaes can use up a lot of the organic waste, but not all of it. Detritus builds up to an extent where you find that the more sensitive animals just won't live, while the animals that normally live in muck--soft corals, mainly--thrive until the tank crashes. JME, of course.
Caesar777 is offline  
post #9 of 13 (permalink) Old 11-07-2007, 06:43 PM
Planted Tank Guru
 
plantbrain's Avatar
 
PTrader: (267/100%)
Join Date: Dec 2003
Location: The swamp
Posts: 13,609
If the growth is slowed via less light, no CO2, then you need no water changes, waste is less than the demand, and we can add a bit of ferts to ensure plants stay healthy, then export/trim them as needed.
It really depends on how impatient you are.

We want the plants to grow faster, so adding CO2 will increase rates by 10-24X. We add ferts like in farms to grow the plants faster than naturally enriching the soil over many decades.

As far as "inventing", I never invented water serial dilutions, nor did I invent dosing fertilizers. I promote and advocate using them to avoid water testing and keep the tank clean. I've always suggested 50% weekly water changes since I kept fish in the 1970's. Never had an issue, easy, simple to do, same with the clients, customers, LFS I worked at as kid etc
Certainly easier than learning testing, water chemistry and doing all that.

I can automate a water change, I can make that very very easy, anyone with a little plumbing skills can for that matter, I cannot automate water testing.

As far as extreme, nothing like hyperbole, Discus keepers routinely do 50% 1 to 2X weekly, some even more, so do most fish breeders. Amano does weekly 50% water changes etc. I guess Amano, Jeff Senske, David Oliver, myself, most every ADA contest winner in the top 100 are "extreme".

Maybe it's not "extreme" and that there's some good common sense to it is more likely the case..............

As you gain skill, you can get away with less frequent water changes, the time difference between 50% and say 20-30% is not that much, and I clean the tank, trim, clean the filters and other general maintenance while the tank refills. I'm not sitting there, waiting................it's also a lot easier to work and trim on a tank with 50% of the water out of the way.
Still, I have little issue eye balling the plants, the tank's health and deciding if I can avoid a water change, and I do sometimes, I've gone many weeks without any on CO2 enriched systems. We all do.
But there is less risk for anyone with more consistent frequent care.

That is just plain simple common sense.
But there will be those that argue against such common sense.
How can I argue with that? hehe

Nano reefs do not need skimmers and all the equipment if they simply do weekly 50% water changes either. Same for larger reefs, but the salt cost $$ and the water needs pre mixed. But it is far simpler and rules out many unknowns. Still, for smaller systems, water changes makes life quite easy and the tank's health very nice indeed.

Regards,
Tom Barr








Regards,
Tom Barr




Regards,
Tom Barr
plantbrain is offline  
post #10 of 13 (permalink) Old 11-07-2007, 09:02 PM
Planted Tank Guru
 
waterfaller1's Avatar
 
PTrader: (70/100%)
Join Date: Jul 2006
Location: Florida
Posts: 5,310
Send a message via AIM to waterfaller1
I guess I am a wc fanatic. Particularly on my reefs. Not only to export nutrients, but to replace necessary trace elements the corals use on a daily basis. Let's face it, on a large reef a 10 or even 20 % wc every two weeks is only a drop in the bucket. On my 12 gal nano I do a 2.5 gal wc every week, since I don't dose it like the 90 w/ refugium/sump/skimmer. I can only export nutrients via the chaetomorpha once a month or so. On fw tanks I syphon out leaves that may die, waste from fish,snails & shrimp throughout the week. And still do a 50% wc on the weekend.
waterfaller1 is offline  
post #11 of 13 (permalink) Old 11-08-2007, 02:06 AM
 
PTrader: (2/100%)
Join Date: Aug 2007
Posts: 97
Huge wc's on sw = surefire failure. Instead, keeping things more constant--a 10-20% weekly, but being sure to get the detritus--is key. Thus, along the same vein, lack of skimmer will also run you into trouble, but that's another topic for another forum.
Caesar777 is offline  
post #12 of 13 (permalink) Old 11-10-2007, 06:00 PM
Planted Tank Guru
 
Robert H's Avatar
 
PTrader: (31/100%)
Join Date: Apr 2003
Location: Salem Oregon
Posts: 2,328
Geez Tom, you always seem to want things both ways. Everyone that follows your "Estimated index" method of fertilizing knows for what the past three or four years, that the biggest part of it is WEEKLY large water changes. That is what has always been the most controversial part of your system that has been heavily debated. Now you want us to believe that it is normal to do 50 to 75% water changes on a weekly basis even if you are not fertilizing? I know Discus breeders that don't even change their water that much!

Robert Paul Hudson

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Kindness like love is unconditional
Robert H is offline  
post #13 of 13 (permalink) Old 11-10-2007, 06:18 PM
Planted Tank Guru
 
frozenbarb's Avatar
 
PTrader: (51/100%)
Join Date: Dec 2006
Location: USA NY
Posts: 2,332
Send a message via AIM to frozenbarb
Sounds pretty normal. Get rid of excessives stuff.
Everyone got difference points of view. Hey it gets rid of algae in my dads Arowana tank.

What seems normal in one persons mind may seem strange in another

One month in.
frozenbarb is offline  
Reply

Tags
None

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the The Planted Tank Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome