maximum safe water change

[coolwaters]

i need to do a massive water change. what amount is safe to do?

 

going to match up the salinity and temp.

 

dont ask me why the water is just #@$@#!@ dirty.

[farkwar]

Brandon does almost 100% water changes on his picos. He leaves just a little bit of water in the bottom for the fish to breath.

 

The MBA does a 100% water change on their kelp tank each night.

 

So theoretically, any size water change is possibly safe.

[coolwaters]

i guess i'll start with a 50% for now. and then another 50% in about 3 days.

 

100% makes me kind of nervous.

[neanderthalman]

If it's an emergency, ie: contamination event, broken heater, then I'd do a 100% water change today, tomorrow, and the day after.

 

I'm not kidding. It's not without risk, but it's many times better than the risk from contamination.

 

If you're just having water quality issues (ie: been a while), then there's no need to be so drastic. Your 2x50% is probably a good start.

[Urchinhead]

Make sure the temp/pH/dKH are in line with what is in there now and you can do up to 100% changes as needed. As a rule of thumb >=1% daily, 10%-20% weekly/bi-weekly, 20%+ Monthly. Best to do weekly if you can.

[lakshwadeep]

Make sure the temp/pH/dKH are in line with what is in there now and you can do up to 100% changes as needed.

 

^^^

This.

[nemmy]

2 50% water changes dont equal 100% just fyi.

It will def help for normal param problems, but if something is REALLY wrong 100% would fix it quick.

 

Say you had 40ppm nitrates, 50% water change would bring you to 20ppm. Then a second 50% water change would bring you down to 10ppm nitrates.

But a 100% water change should bring you to 0ppm nitrate (as long as you dont stir up the sand bed or there isnt nitrate thats going to leach out of the rock).

[Apoptosis]

2 50% water changes dont equal 100% just fyi.

It will def help for normal param problems, but if something is REALLY wrong 100% would fix it quick.

 

Say you had 40ppm nitrates, 50% water change would bring you to 20ppm. Then a second 50% water change would bring you down to 10ppm nitrates.

But a 100% water change should bring you to 0ppm nitrate (as long as you dont stir up the sand bed or there isnt nitrate thats going to leach out of the rock).

 

Yes, 50% + 50% = 75% reduction of your old water (and whatever is in it)

[StevieT]

99.3% don't go higher