Water change question

My nitrates are on the high side and i want to lower them. Is it better to do a larger percent water change once or a lower percent a number of times?

 

I would do a larger change. If you think about it mathematically, you are changing less of the "bad" water every time if you do a number of small changes. Once you do a small change, you are actually removing a smaller percentage of the "bad" water every time because the new water is mixed into it....make sense?

 

Depends on if its a newer tank or an older tank really. If its a tank that is still in its cycling process. Than its normal and I wouldn't really touch it. But all in all, its usually better to change small amounts once an hour to get the levels down. Don't change an extreme amount of water as it can change the balance in the eco dramatically and it will do a mini cylcle again


Conrad

 

i was thinking like a 20% water change. Should it be more or less?

 

Oh. A 20% water change will be fine as its not too high or too low. That will do the fix just fine. If its not down within an hour(Wait on testing as the water needs to circulate for a little while). Than you can do another water change to bring it down till its in a safe level.

 

20% wont hurt anything. It's the 50% changes that shock your livestock. I do 20% changes every week

 

A 20% change is good....I wouldn't do too much more then 30%. That should fix it. I would wait a couple of hours after that and test your water again to see what your parms are. If that didn't do it, then I would change about 10%-20% again. Ultimately, you need to make sure you are in a good habit of making your water changes...otherwise, you will have this problem and many others. Also make sure you are using RO water, it is typical for NO3 to be in tap water if that is what you are using.

Is your tank cycled or going through its cycle? If it is not that old, it may be going through a second cycle depending on what all you have in it and how old it is.

 

the tank is cycled. its been established for a year or so. I do water changes every thursday.

 

I think you should first worry about locating where this problem is originating rather than trying to mask it. If the tanks a year old you shouldnt really have a nitrate/nitrite (forget which one) spikes. Maybe your overfeeding? do you use tap? do you use carbon? if so, how recently do you replace it?