WATER CHANGES: How much/often?

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largemouth said:
I know, it's funny. Some of the things already mentioned in this thread are great ideas that I had never even thought of. Like pumping the water through the python out of a bucket. The place I am living right now (moving this weekend) has a faucet that is the biggest pain to attach the python to, but I had never even thought of doing it another way. I always just fight the faucet until it gives up. :rolleyes:

I gave up fighting the faucet. After countless trips to Home Depot and Lowes to find an adapter and many hair pulling attemps to make a DIY adapter. I gave up. Hence the bucket Idea. LOL!
IMO it might actually do better than faucet direct. The fall of the water from the faucet spout to the bucket creates water turbulence and added aeration before being pumped back into my tank.
 
Ha! We AIMed about this very topic last night. I do 40-60% water changes every 2 weeks on my tanks. For my larger tanks (360, 180, 100), I do gravel vacuuming into 5 gallon buckets and siphon the remainder out the window with either a 1 1/4" ID siphon or 3/4" ID siphon, depending on how impatient I am. For my smaller tanks, I just siphon with the gravel vacuum into buckets and dump them on my lawn. I refill using a Python and a ballpark estimate ("hand in water") of temperature. It takes a LONG time to refill 50% of the 360 gallon, so I pass that time by scrubbing algae in my other tanks and sipping on beer.
 
Ya it is true that most of the bacteria you care about is in your gravel and filter media. But it just depends on your water chemestry. Like I said if you use Co2, the Co2 lowers the pH, and when you do a huge water change like 70% it will flux up to where your tap water is, this also applies to methods of hardening and softening your water.

I just think that 70% is maybe too shocking for some fish, I prefer a less intense change, although for some big, dirty and hardy fish, thats probably just what the doctor ordered.

I actually think I have a pretty unique method of water changes on my 10g planted tank that I'll share.

I use a python to suck the water out and down my sink. Then since its a planted tank, and my tap water is hard and has a high pH I use a 50/50 RO and tap water mix, this gets my water chemistry to right where I want it.

I pre mix that water and keep it in a 5g bucket in my room. Then since it gets pretty cold in Minnesota in the winter I put a submersible heater in the bucket and put the lid on the bucket then it keeps the temp right where I want it. Then if I need to do a water change or a top off, I can't just pour the bucket into the top of the tank. I just scoop a cup from the bucket on top offs.
 
Griggs said:
I also use the python to change water. But I think 70-90% is way to high. You change 20-40% and 40% only for really messy tanks/fish.

Your taking too much established water out. If your doing a planted tank with Co2 you could have a real problem with pH changing too


70-90 is not too high, infact its perfect. IF and ONLY IF the water you are putting in contains roughly the same GH, PH and Temp as the water you took out. other wise it will shock the fish mildly.

Incorrect about the planted tank. If you are using a Co2 Injection system it will replace the Co2 you took out. Co2 Is not a important/detrimental factor like Ph or GH. the plants can go quite a while without a shot of Carbon dioxide.

when you do a large water change besure to get the PH, GH, and Temp roughly the same.
 
JacksPets06 said:
At work we are supposed to reccomend doing about a 30% water change cleaning out the gravel really good with a gravel vac about once a month. I however dont do them that often, especially on my saltwater because I have so much liverock in my tank. I dont believe that taking out so much water will take out all the bad bacteria, because it also takes out the good bacteria that is established... But other then that, I think about 30-40% is good enough.

30% once a month is NOT enough and furthermore not helping your system at all. Nitrates are being produced daily, so is the lowering of the PH as the acid byproducts build up and neutralize your KH. You should be doing water changes weakly. you should be completely turning over your tank volume with NEW water every 2 weeks. unless, of course, its a self sustaining system like a professionally done Reef tank.

Bad bacteria? what are you talking about. that has nothing to do with water changes. Water changes are not intended to "sanitize" the system from these so called "bad" bacteria. the True intent of a water change is to cleanse the system from Ammonia, Nitrite, and the high build up of Nitrate. Aswell as replenish the dropping PH and KH.

also, You are not effecting your biological "bed" by taking out the water.. they are not present in the water, infact they are stuck to the surface areas inside your tank. Nitrifying bacteria are not "floating amock".
 
Griggs said:
Ya it is true that most of the bacteria you care about is in your gravel and filter media. But it just depends on your water chemestry. Like I said if you use Co2, the Co2 lowers the pH, and when you do a huge water change like 70% it will flux up to where your tap water is, this also applies to methods of hardening and softening your water.

I just think that 70% is maybe too shocking for some fish, I prefer a less intense change, although for some big, dirty and hardy fish, thats probably just what the doctor ordered.

I actually think I have a pretty unique method of water changes on my 10g planted tank that I'll share.

I use a python to suck the water out and down my sink. Then since its a planted tank, and my tap water is hard and has a high pH I use a 50/50 RO and tap water mix, this gets my water chemistry to right where I want it.

I pre mix that water and keep it in a 5g bucket in my room. Then since it gets pretty cold in Minnesota in the winter I put a submersible heater in the bucket and put the lid on the bucket then it keeps the temp right where I want it. Then if I need to do a water change or a top off, I can't just pour the bucket into the top of the tank. I just scoop a cup from the bucket on top offs.


You should be adding things to your tank to help combat the dropping PH. If you dont do water changes or add buffering agents to your tank the Co2 will drop the PH into very acidic levels which will kill your fish. Most advanced Planted tank keepers will keep crushed coral in their filters. this helps baddle the Co2. they also have a regulating system that will shut the Co2 OFF if the PH drops below a certain level, When the Co2 is off the crushed coral will start to bring the PH back up which then the regulater starts injecting Co2 again.

They keep their Tank at a certain PH and when they do a water change they only add in the same ph as their tank. This is what you should be doing. Not adding in Different parameters into your tank. You should try and get your tank at a certain level and maintain it.

If your Planted tank has a PH of 6.5 and this is where you WANT it, you should not be adding new water in with the PH of 7.0. You should be mixing the water with a PH lowering agent in a bucket to get it to 6.5, and then add it in.
 
Griggs said:
I just think that 70% is maybe too shocking for some fish, I prefer a less intense change, although for some big, dirty and hardy fish, thats probably just what the doctor ordered.
.


1 more thing.

water changes will not effect the fish unless the Parameters are different. Most pro Discus breeders perform 100% water changes a day with no ill effects to the fish. Not to mention discus are one of the most sensitive freshwater fish, when it comes to water quality.

If the parameters are the same or very close, it will not effect the fish.
 
PeacockBass said:
30% once a month is NOT enough and furthermore not helping your system at all. Nitrates are being produced daily, so is the lowering of the PH as the acid byproducts build up and neutralize your KH. You should be doing water changes weakly. you should be completely turning over your tank volume with NEW water every 2 weeks. unless, of course, its a self sustaining system like a professionally done Reef tank.

Bad bacteria? what are you talking about. that has nothing to do with water changes. Water changes are not intended to "sanitize" the system from these so called "bad" bacteria. the True intent of a water change is to cleanse the system from Ammonia, Nitrite, and the high build up of Nitrate. Aswell as replenish the dropping PH and KH.

also, You are not effecting your biological "bed" by taking out the water.. they are not present in the water, infact they are stuck to the surface areas inside your tank. Nitrifying bacteria are not "floating amock".



well what fish does he have
my dad has oscars in a 150
and he does around 30 once a month
 
rayman45 said:
well what fish does he have
my dad has oscars in a 150
and he does around 30 once a month


It doesnt matter what species of fish he has. The species of fish wont have anything to do with the toxicity of the Nitrate, ect ect.

what is your point?
 
im saying oscars are one of the most dirty fish there is
they are growing fine with 30% a month


now on the other hand if you had rays 30% a month would kill them before you have a chance to change the water


my dad has 4 oscars(sold of 2) 1 gt and 1 blue channel cat in a 150
he has 2 404's on it and 2 powerheads
 
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