You actually have to be quite careful and patient with water changes as a rapid change to water composition (chemicals, temperature etc) can stress them out to the point of death.
It also depends on how much water you have and how many tadpoles you have in it. As well as if you have an air pump and filter. I would recommend about two to three litres of water per tadpole, an air pump and filter will reduce the yucky stuff in the water so you don't have to change the water as often as well as oxygenating it so the tadpoles don't suffocate.
If you have a large body of water with an air pump and filter you can get away with %10-%20 water change once a week. I just use a clean coffee cup (you just need to measure how much you take out and out in) and for my 20 litre tank I take about five cups of water out and put in the same amount of dechlorinated water (also watch the PH balance as most amphibians are happiest at PH 7.0 (neutral) you can buy PH testing kits and PH uppers and downers from you local pet shop)
If you have a large body of water with no air pump (not recommended) you will need to do a %10-%20 water change daily, however this needs to be done slowly. Say if you are doing a %20 change, take out %10 and add in the %10 of fresh water then wait for 30min - 1 hour before doing the other half.
You can also buy 'oxy shells' which are little round white things, get them from pet shop, that release oxygen into the water, cheaper then an air pump but they do need replacing. I have one in my froglet tank, this is for my guys that have all their legs but still have their gills so are in a small amount of water with a few rocks which come above the surface for them to gain easy access to dry land for when they begin climbing.
For a complete water change (all of the water needs changing) fill up a empty clean (just use boiling hot water, no detergents) bucket and fill this almost all the way up with old water scooped out from the tank, be careful not to bump of knock you tadpoles while you scoop out the water as this can cause deformities or even death. Then place you tadies in the bucket of the tank water. This can be very stressful for them so it is best if you can transfer them from the tank into the bucket in the same water that they have been in (easy as you can scoop them up from the tank using a cup, with the tank water, also don't pour them into the bucket, submerge the cup with water and tadpole in it and let the tadpole swim out)
Now with all your tadies in the bucket you can empty the tank and clean the stones etc.
Fill the tank back up to the appropriate level with dechlorinated water (now the tricky bit) very slowly (over a long period of time) take out say three cups of water from the bucket, chuck it out down the sink etc, and replace it with three cups of the fresh tank water. Then leave it for about an hour or so and repeat until most of the water in the bucket is now the fresh tank water. Now it should be safe to carefully place the tadpoles back into the tank. Again don't pour them out of the bucket.
Complete water changes should be done every two to three weeks, more regularly (say every week to two weeks if your do not have a filter as tadpoles produce ammonia and are very messy creatures).
It also depends on how much water you have and how many tadpoles you have in it. As well as if you have an air pump and filter. I would recommend about two to three litres of water per tadpole, an air pump and filter will reduce the yucky stuff in the water so you don't have to change the water as often as well as oxygenating it so the tadpoles don't suffocate.
If you have a large body of water with an air pump and filter you can get away with %10-%20 water change once a week. I just use a clean coffee cup (you just need to measure how much you take out and out in) and for my 20 litre tank I take about five cups of water out and put in the same amount of dechlorinated water (also watch the PH balance as most amphibians are happiest at PH 7.0 (neutral) you can buy PH testing kits and PH uppers and downers from you local pet shop)
If you have a large body of water with no air pump (not recommended) you will need to do a %10-%20 water change daily, however this needs to be done slowly. Say if you are doing a %20 change, take out %10 and add in the %10 of fresh water then wait for 30min - 1 hour before doing the other half.
You can also buy 'oxy shells' which are little round white things, get them from pet shop, that release oxygen into the water, cheaper then an air pump but they do need replacing. I have one in my froglet tank, this is for my guys that have all their legs but still have their gills so are in a small amount of water with a few rocks which come above the surface for them to gain easy access to dry land for when they begin climbing.
For a complete water change (all of the water needs changing) fill up a empty clean (just use boiling hot water, no detergents) bucket and fill this almost all the way up with old water scooped out from the tank, be careful not to bump of knock you tadpoles while you scoop out the water as this can cause deformities or even death. Then place you tadies in the bucket of the tank water. This can be very stressful for them so it is best if you can transfer them from the tank into the bucket in the same water that they have been in (easy as you can scoop them up from the tank using a cup, with the tank water, also don't pour them into the bucket, submerge the cup with water and tadpole in it and let the tadpole swim out)
Now with all your tadies in the bucket you can empty the tank and clean the stones etc.
Fill the tank back up to the appropriate level with dechlorinated water (now the tricky bit) very slowly (over a long period of time) take out say three cups of water from the bucket, chuck it out down the sink etc, and replace it with three cups of the fresh tank water. Then leave it for about an hour or so and repeat until most of the water in the bucket is now the fresh tank water. Now it should be safe to carefully place the tadpoles back into the tank. Again don't pour them out of the bucket.
Complete water changes should be done every two to three weeks, more regularly (say every week to two weeks if your do not have a filter as tadpoles produce ammonia and are very messy creatures).
