In the past years, I tried to go as low tech as possible and did not change water in my community tank for months. Some of my friends of similar direction bragged that they did not change it for a year, or so. We only added water or replaced about 10-15% of it after siphoning out the muck. There were no water filters used. The added water was a regular tap water, but more oftne it was distilled water. The tank size was about 30 gallons. Plants used were fast groing ferns, Ceratophyllum demersum, Aponogetons, Echinodorus spp. and crypts. Fish community was mainly of tetras. Now I have a water filter Aqueon brand. In a new established 30 gallon tank the water returned to crystal clear in about a month. Blue green algae started to grow, but it seems they are on the decline already. In this tank, I have only platies so far, but after a while I will buy some tetras again, some freshwater shrimp and a pair of kribensis. Only black physa snails are allowed in the tank; I do not like when snails eat my plants. I am going to resume the same "no water change" method. Of course, the feeding should be done very carefully, mainly live food is used and behavior and condition of the fish should be watched carefully. To me, this is an intersting way of keeping the system in balance. I do not want to teach everyone else to do what we do, but I post it, because I found that very many aquarists partially replace water very often.

I do a water change every week. I have a 36gal tank and I fill a 5gal bucket once. So i figure thats alittle more than 10% weekly.

I think when the 88gal is setup and has fish, I will try some other alternative methods to water changes.

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Way more often than your setup. There is another poster on this forum who doesn't do wc's be he's in the minority. I do at least 25% every week but some of my tanks are planted and some not.

Other than the bit of work involved, which I don't mind, what is the advantage?

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60g tall, all artificial plants, Rainbow tank; 55g for African Cichlids. 20g long for fry; 20g hex, 2 black Angels at my desk; 10g planted, with 50 Molly fry; 10 gal, 2x 13w cfl lightning, planted; 2g hex for "Buddy the Betta"; Wanting a 200g +, MTS getting bad.

Test your water, I would bet it is very high in nitrates. Some fishes don't mind them, others it kills. My experience with Kribs is they don't like high nitrate water and they develope pop-eye. Angels and Discus also don't like high nitrates. The natural environment for many of our Tropical Fish is subject to very high rainfall rates so they are exposed to a constant flushing of fresh water.

My planted tank get waterchanged ever 4-6 weeks, non planted every 3-4 weeks. Fry tanks, depends on the fry.

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1x350L Goldfish, 1x 286L Planted, 1x190L Cherry shrimp, 1x140L Feeders, 1x130L Planted, 1x119L Peppermint BN breeding colony

I do 60% weekly on all of my tanks. Personal choice/preference for any of it. Necessity for some.

I EI dose,so 50%weekly.Moderately planted,and very understocked and over filtered.

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http://bountifulbettas.blogspot.com/

"Come to the dark side....we have cookies...and filters/heaters/and water changes!"

My answer about nitrites, nitrates and all kinds of toxic fish metabolites. Actually, we never measured nitrites level in water at that time. However, we tried to imitate natural systems by keeping a combination of fast and slow growing plants and sufficient lighting. The plants were Ceratopteris thalictroides of both floating and semifloating forms and hornwort. They extracted nutrients from water. We also had echinodorus and crypts of several species, which develop good roots and extracted nutrients from the gravel. We watched so the pants had enough light and grew well, and the fish behavior was normal and even enjoyable to watch. Our major focus were tetras, which like old slow or stagnant water. The "rain" was when we cleaned the muck from the bottom and repalced it with distilled water. Sometimes it triggered spawning behavior in fish. Our tetras were happy, because we bred them successfully and rarely bought new ones. Our favorite species were: neon tratra, glowlight tetra, head and tail light tetra, black skirts, flame tetras and serpas. We avoided overcrowding in the community tank, fish density was not higher then 3 liters of water per one fish. Aeration was moderate, because tetras do not like much turbulence and there were no water filters at that time. The food was mainly small crustacea collected live in ditches and lakes with nets. This is the cleanest way of feeding aquarium fish without polluting the water. At a later time, I moved in Virginia and still cannot find a pothole with natural foods, only fast running stream. Our own pond does not help, because I have catfish and gold fish in it, which ate all naturally emerging crustacea. I would say this is a kind of art to keep the system in balance with a minimal intervention in a form of massive water replacement or rearrangements in the substrate and flora in the tank. It takes not as much labor, but it takes a lot of carelul observations and patience. Tetras are happy under such conditions and look fantastic in small schools up to 5-9 fishes of each species. At a later time, I switched from tetras to bettas, gouramis and livebearers. I am breeding them, too, but they are not as picky about water quality.

Good morning ufimych. Water changes will depend entirely on you. How often do you want to change the water???

I have large tanks with a lot of fish and plants, so I do a 50 percent change about every three to four weeks. None of the tanks is heavily filtered. I don't test my tank water, because I know after years of doing my tanks, if I stick to my water change schedule, the water conditions are fine for my fish.

Your post reads like you're doing something similar. However, I don't think any tank is completely self sufficient.

B

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Low Tech Water Building Keeper

50% twice weekly on the 210g discus,
20% weekly on my 75g although I am pushing this one off as it is planted and will be even heavier planted come this weekend when I take in over 100 plants.

Ive got a 10g tank that I just add water to, its for my gupps but weekly and twice a week testings show fantastic readings.

I have not done a regualr water change in my FW or marine tanks since the late '70s. Just replace evaporative water with straight untreated tap.

tanks have lasted up to 8 years. FW with descendants from the original fish. Marine with fish 5 years olds.


my .02

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fw leiden since 1979, fo salt since 1979, mixed reef 55g 2002-2009. Strong emphasis on the tank taking care of itself. Balanced with plant life, no water changes, tap water, no filters in FW. Only dosing calcium, alk, mag in marine reef tanks. http://www.aquariumforum.com/f15/my-...ods-26410.html
recent tanks (till 2009) 7 years- 10g FW leiden 7 yrs, 55g mixed reef 7, 2 yrs, 20g FW leiden, 10 g fw leiden , 29g mixed reef, current tank 55g leiden

Bob, all your tanks or are all your tanks on a living substrate?

all of the tank were balanced out with plant life (FW plants, marine--various algaes/macros).

using substrate materials from building supply stores. No live sand or the like.

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fw leiden since 1979, fo salt since 1979, mixed reef 55g 2002-2009. Strong emphasis on the tank taking care of itself. Balanced with plant life, no water changes, tap water, no filters in FW. Only dosing calcium, alk, mag in marine reef tanks. http://www.aquariumforum.com/f15/my-...ods-26410.html
recent tanks (till 2009) 7 years- 10g FW leiden 7 yrs, 55g mixed reef 7, 2 yrs, 20g FW leiden, 10 g fw leiden , 29g mixed reef, current tank 55g leiden

Of course, this is an important part of the beauty of this hobby; biodiversity, diversity of tastes and methods of management of aquaria... I have a taste to tetras and try to adjust the environemnt for them. If I want another fish, it has to adapt to what I have, or I will find another one, which would better fit my environment. My gravel is nearly white, very dismal to me; I had bought it used. I hope it will become darker with time. In a few days, I will go and buy some Characidae fish. Water filters are wonderful. This is my first one and it did the job very well. Perhaps, with this thing, I will age water in my tank much faster.