Questions about water changes.

[GouramiFanatic]

I'm just wondering how everyone else does their water changes. I've had a lot going on lately and haven't been able to keep up with my normal water changes. I try to do at least one good one (est 40-50%) every other week or so. This includes a gravel vac and I also try to get under as much of the decor as possible as well. Once I'm done the water change I shut the tank lights off while it's filling back up in attempts to keep the fish's stress levels down. I'm just wondering what routines everyone else falls under, so here are my questions...

• How often do you test the water parameters?
• How often do you do a PWC?
• How much of a PWC change do you do (%)?
• Do you move the decor around to vac under it?
• Do you shut the tank lights off while it's filling up?
• How long do you want to retest the water?

 

[neilanh]

How often you test your parameters is really dependant upon how long your tank has been running. Eventually you'll know that things are stable and can cut back on how often you test.

PWCs are good, no matter how you slice it. Some do them weekly, some monthly. It's never a bad thing.

Anywhere from 20-50% is common for freshwater tanks when doing a PWC.

It is a good idea to vacuum under your decor occassionally, as gunk will build up under there that you'll want to take out.

Typically I leave the lights on. The fish will learn to enjoy PWCs, and mine come and play in the water when I'm doing them.

 

[peaceablegarden]

I'm relatively new but have learned a lot in the past several months. My tanks are doing fairly well (are stable) and find that I only test occasionally or if something seems wrong. I do weekly pwcs of about 15-20% and vacuum at the same time. My fish also seem to enjoy having the water cleaned and will come and get as close as they can. It's kind of funny. I have two platy fry that get right up near the vacuum end almost like they want to get sucked up. I guess I've just started to get a feel for what's what in the tanks. Everybody looks happy and healthy so I don't test. Someone looks a little under the weather, water changes color, or seems overly dirty then I test. Or just for good measure about once a month or so.

 

[Mudfrog]

All of my tanks get a 50-75% WC each week. As for testing the parameters, if it's a new tank I'll test it every week once it has cycled. I do not test the water on my older tanks unless I think something is wrong.

 

[amosf]

25-50% per month is enough in a established tank. More often doesn't matter.

testing isn't a big issue on established tank, but again doesn't hurt to check, esp is something doesn't look right, like if it's cloudy.

I vac what i can in the planted tanks and lights stay on... fish don't worry much.

 

[FishCrazyBenBOMB]

I do around 40% WC when it looks like it needs it. I never test my water so I don't worry about that. And all of my tanks are sand bottom now so no need to vac gravel.

 

[Mudfrog]

25-50% per month is enough in a established tank. More often doesn't matter.

testing isn't a big issue on established tank, but again doesn't hurt to check, esp is something doesn't look right, like if it's cloudy.

I vac what i can in the planted tanks and lights stay on... fish don't worry much.

This isn't the case.. It depends on a lot of factors.. the bioload plays a huge role. An overstocked tank will need a lot of big and frequent water changes.

 

[buddha_red]

i change 20% weekly, i have two buckets that are the same. fill one, empty one

 

[Johnny Tuttle]

I do 50% every week, and sometimes, I just add in a smaller one (20-30%) midweek, as I don't see how it can hurt if I'm careful to match the temperature of the new water.

More is better.

 

[amosf]

This isn't the case.. It depends on a lot of factors.. the bioload plays a huge role. An overstocked tank will need a lot of big and frequent water changes.

only if the bioload is grreater than the ability of your 'filter' (bacterial colony) to cope. By established I also mean stable.

My tanks are overstocked by the standards here. bioload is handled well by the system and monthly water changes are more than enough.

Want to change more often, go for it. And if you have a poorly balanced system then sure, change more often.

 

[marchmaxima]

Ido 20% pwc's weekly. My tank has been established for around 12 months now and is stable so I test monthly just to ensure everthing is in check.

 

[JasonC]

I'm at 25% PWC and gravel vac every week. Water tests every 3 days. I've only been established for 4 months though. One curiosity, even after I gravel vac, I am getting a cloud of debris when I refill. Somewhat normal? Or do I need to think about doing a heavier/more frequent cleaning schedule?

 

[Mudfrog]

I'd be curious to see what your nitrate level is after a month. If your tank is overstocked the fact that the bacterial level can handle the conversion to Nitrates is only part of the equation. You will still have an abundance of Nitrates (especially on overstocked tanks) and the only way to remove those Nitrates is with water changes.

 

[BillD]

Have to agree with Mudfrog here. For anyone to arbitrarily say "you only need to change X amount monthly" is just wrong. Personally I try to do 50% weekly, but if I miss a week, it's no big deal because I am changing more than the minimum. Every tank is different so making blanket statements, which some might take as facts, is wrong. I know of no fish that thrives in dirty water, but I can assure you that fish do better in clean water. They grow more quickly for one thing, and if you want to see how quickly water quality can affect fry, try to grow out some angels without large (50% or more) frequent water chnges.
Having been an aquarium society memeber for about 15 years, I have had occasion to cross paths with a lot of "expert" fish keepers/breeders, and the one constant with all of them, and some have in excess of 100 tanks, is large frequent water changes. So, while while some fish will survive with less than optimum water conditions (they are very adaptable) all wil do better in clean water. Keep in mind that while nitrate levels are used to determine when water needs to be changed, there are many other noxious compounds found in aquarium water that should be removed, and aren't tested for.

 

[GouramiFanatic]

Thanks for the input so far everyone! It's always interesting to see the different methods and routines that people use when keeping tanks. Seems as though everyone has success doing things their way which is why it remains "their way". My routine of doing a large PWC (40-50%) every other week or so has brought me great results. I have healthy fish and they appear to be pretty happy to me. The death rates in either of my tanks is very low with none in recent memory.

I'd be curious to see what your nitrate level is after a month. If your tank is overstocked the fact that the bacterial level can handle the conversion to Nitrates is only part of the equation. You will still have an abundance of Nitrates (especially on overstocked tanks) and the only way to remove those Nitrates is with water changes.

Was this directed at me or someone else? Are saying my tank is overstocked? I've had good test results when I do them so I never considered it to be overstocked.

 

[amosf]

hehe.. well I've been around a while as well what you find is the extremes both ways on forums like this... those who change weekly and those who rarely change water. And no, you don't see a huge nitrate buildup in a month. Sure.. things have changed a lot over the 35 years or so I've been doing it... Back when I started it was more like a water change every 6 months - or more

50% weekily is more than you need to change to have healthy long living fish. It's fine for people to do so, but I there is no point making people feel guilty if they only change monthly with a stable established tank. I have tanks with breeding populations, spawn, fry and grow old, and no major indications or high nitrates on tests, so monthy is certainly a viable wc regime.

Likewise the fish appear 'happy' and healthy with low deathrate, tho happy is an interesting concept with fish anyway, it's been a long long time since I lost a rainbowfish... or goldfish - and I don't see too many others floating arround

 

[Mudfrog]

Was this directed at me or someone else? Are saying my tank is overstocked? I've had good test results when I do them so I never considered it to be overstocked.

Nope, not directed at you

 

[Mudfrog]

hehe.. well I've been around a while as well what you find is the extremes both ways on forums like this... those who change weekly and those who rarely change water. And no, you don't see a huge nitrate buildup in a month. Sure.. things have changed a lot over the 35 years or so I've been doing it... Back when I started it was more like a water change every 6 months - or more

50% weekily is more than you need to change to have healthy long living fish. It's fine for people to do so, but I there is no point making people feel guilty if they only change monthly with a stable established tank. I have tanks with breeding populations, spawn, fry and grow old, and no major indications or high nitrates on tests, so monthy is certainly a viable wc regime.

Likewise the fish appear 'happy' and healthy with low deathrate, tho happy is an interesting concept with fish anyway, it's been a long long time since I lost a rainbowfish... or goldfish - and I don't see too many others floating arround

I'm sure most of us have been keeping tanks for a long time

But I'm curious as to what your nitrate level is when you do change your water once a month. I do 50% WC on my tanks because I like keeping my nitrates under 15ppm. This ensures it stays low. I also understock my tanks. Even with my tanks being understocked I would think if I went a month without any water changes then my nitrates would probably be in the 50-75ppm range, thats not a very healthy range for fish.

Take my 120g for instance, it's running a 29g sump with TONS of biomedia. I have one 7.5" Dovii in that tank, that is the only fish in there. But after one week my Nitrates are up around 12-14ppm. So imagine if I went 4 weeks without doing a water change, it would be up over 50ppm. And that is in an extremely understocked tank

 

[GouramiFanatic]

Take my 120g for instance, it's running a 29g sump with TONS of biomedia. I have one 7.5" Dovii in that tank, that is the only fish in there. But after one week my Nitrates are up around 12-14ppm. So imagine if I went 4 weeks without doing a water change, it would be up over 50ppm. And that is in an extremely understocked tank

This is inexperienced side of me speaking here... How do you figure out what the bioload is. Do you basically look at the nitrates to figure out when you have enough / too much in one tank?

 

[Mudfrog]

There really isn't a set formula for figuring out how much bioload you have. Usually the amount of fish / tank size / filtration amount will be a good indicator. If they are not then yes you can tell by testing your nitrates. If it were me I would do a 50% WC then test the nitrate level. After a week test the nitrates again. If your nitrates are high then that would be a good indicator that your bioload is too much for that tank.

Which brings us back to the whole point of doing 50% water changes each week will allow you to have a higher bioload on a smaller tank.