Water change for 39 gallons

1. How often should I WC a 39 gal tank in a week
2. How much water should I replace with new water?
3. How do I avoid stressing my fish and inverts whenever I WC ? specially my tank is a planted one and I use vacuum.

 

1. How often should I WC a 39 gal tank in a week
2. How much water should I replace with new water?
3. How do I avoid stressing my fish and inverts whenever I WC ? specially my tank is a planted one and I use vacuum.

1. once a week should definitely be fine
2. between 30%-50% is a good amount
3. I have no idea

 

1. depends on stocking level and how much nitrates you are building up, there more reason to a water change than just nitrates, but buildup of nitrates is a good indication it's time to change water because other things are being depleted or building up also.
2. Depends on how much you need to do to keep it where you want it to be. Your frequency and volume of water change should be determined by how long nitrates take to build up depending on your stocking level. if you keep nitrates at 10ppm, and it takes 1 week to get to 20ppm, then it would be a 50% change once a week. If it takes 2 weeks to get there, then 50% every 2 weeks or 20% each week. again, there's other things to consider besides nitrate build up with water quality. if your nitrates are slow to build due to planting, low stocking and filtration, maybe consider doing a weekly 10% change just to bring new water into the tank.
3.What inverts do you have? Snails would be different from Shrimp let's say.
But, generally speaking, the more frequent you change water and in smaller amounts, the more used to it the fishy friends become to it happening, the shorter it takes, and the less drastic it is to changing parameters or kicking up a cloud doing it, and the less stressful it becomes because it's routine and small.

my angel juveniles, get a daily vacuum and while they all might splash around if I make a sudden movement near the tank and spook them walking past, they all just move from the vacuum and don't dart around frantically because the vacuum is totally expected and they know if they stay out of the way nothing is going to happen to them, it's not a predator. It becomes part of the decor that comes and goes.

 

There are no firm rules concerning water changes. The two closest things to rules might be these:
1. Make sure you do water changes.
2. If you are seeing problems, you probably need to do water changes more often.

Many people on the forum like to do 50% water changes each week. For smaller tanks 10 gal and under, following this practice is not time consuming. If you had a 200 gallon tank, doing a weekly water change of 50% might be more than you want to undertake, especially if you have to lug buckets of water to and from a sink.

Tetra, the largest supplier of aquarium equipment and supplies in the world recommends changing 30% of the water in the tank every 30 days.That is probably the minimum acceptable practice.

I would suggest that you start off changing 10 gallons of water in your 39 gallon tank each week and observe the results. If the tank remains stable then you might be able to reduce either the frequency or magnitude of the water changes. If the tank is heavily stocked, you might need to increase either the frequency or magnitude of the water changes.

My tap water is so bad that I do not use it for water changes, nor do I use it for drinking and cooking. I use water purified by reverse osmosis and then remineralized. Thus, water changes are more expensive and more time consuming than they would be if I could use tap water. Thus, my plan is to do a 10-15% water change once per week. However, like the 30% per 30 days, doing 10-15% per week is minimum acceptable. Lugging jugs of RO water from the basement up to my tank on the main floor is not my idea of fun.

 

Thankyou guys for the advice. My Tank is heavily stock, so I will take more water out from the tank like RayClem said, while I WC.