Water Change?

[bobbydog]

Hi everyone..im a new member to your exellent forum..ive just recently aquired my new aquarium after many years abstinence..Ive decided to go for a planted set up.The internet is a fountain of knowledge and wasn't around the last time i had an aquarium(yes..thats how long its been).....anyway..heres my question..how much and how often do i change the water on a planted tank.Ive read somewhere thats its 50% per week.This seems really excessive as ive always thought it was 20% once every 2 weeks..Please educate an old school fish keeper..good health to you all

 

[james_fish]

Hi Bobby. It really depends on how much nitrates (end product) are being built up during the week. This can depend on a few things...

1. Whether the stocking is high or low?
2. Whether the fish are messy or not?
3. What volume the tank is? E.g. 55 us Gallons
4. How many plants are in their.

Although Nitrates aren't very poisonous, you never want your level to be over 40ppm as it can start to have an effect on fish. (To test your nitrate, a test kit will be needed) API liquid tests are good to use.

About 30% per week should be enough to keep nitrates down at a safe level. Or alternatively 50% every couple of weeks.

James.

 

[bobbydog]

Hi Bobby. It really depends on how much nitrates (end product) are being built up during the week. This can depend on a few things...

1. Whether the stocking is high or low?
2. Whether the fish are messy or not?
3. What volume the tank is? E.g. 55 us Gallons
4. How many plants are in their.

Although Nitrates aren't very poisonous, you never want your level to be over 40ppm as it can start to have an effect on fish. (To test your nitrate, a test kit will be needed) API liquid tests are good to use.

About 30% per week should be enough to keep nitrates down at a safe level. Or alternatively 50% every couple of weeks.

James.

Thanx for your fast response...so are you saying that more plants should=less nitrates..more fish(fish waste)=more nitrate therefore more regular water changes?

 

[james_fish]

In a simple way yes. But you'll find only some of the best heavily planted tanks will lower nitrates, but in order to achieve this you may need to invest in some very good c02 and a decent lighting system. More fish waste=more ammonia-->nitrite-->nitrate. Like I said the 25-30% weekly should easily be enough

Oh and to the forum

James.

 

[RadaR]

50% water change per week applies to high tech tanks (tanks that are injected with CO2 or dosed with liquid carbon, and regular dosing of macro and micro nutrients).
This gives rise to high plant growth. More plant growth means more plant waste is produced. A build up of organic waste and ammonia will harm fish. This is where the 50% water change per week comes in.
Planted tanks dont do water changes to reduce nitrates, nor stabilize KH. It's all to do with reducing organic waste and ammonia. These ammonia concentrations I'm talking about are two to three orders of magnitude lower than what can be registered on a hobby grade fish kit. The concentrations arent enough to harm fish or shrimp, but they can induce algae spores to bloom.

you never want your level to be over 40ppm as it can start to have an effect on fish.

There has been no scientific study on tropical fish that shows this. Also, the test kits we have (even API) for nitrate are awful. They are consistently in-accurate. A reading of 25ppm could be anyway between 0.25ppm and that.

To the OP, if you dont want to do 50% water changes per week then have a low tech tank. One light tube above the tank, no CO2, no nutrients. Simple

 

[james_fish]

you never want your level to be over 40ppm as it can start to have an effect on fish.

There has been no scientific study on tropical fish that shows this. Also, the test kits we have (even API) for nitrate are awful. They are consistently in-accurate. A reading of 25ppm could be anyway between 0.25ppm and that.

Well, thats going by just what i've heard. I've heard that long times of nitrates above that level can effect fish.

James.

 

[bobbydog]

Im learning fast thanks to you all

 

[RadaR]

bobby, I'm sure you will find this link useful.

 

[bobbydog]

Thanx RadaR...i love this site