Big water change?

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dtd87

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Assuming I have the salinity and temp the same it is safe to do say a 50% water change?
 
Not a problem at all. Good way to get rid of some nasty stuff and dilute some water quality issus . I know a member here who over the course of a week use to do a 100% water change. Not a problem once the temp, salinity etc are all the same. :)
 
Yep... ive done 80%+ at times... several times a week, as long as your using good salt.. and you have your levels right... its on
 
Ok, here is my questions.

What type of media are you using? Live Rock with Fish Only or Fish only? I recently tored down a very expensive Tank. It was using Bio Balls with Wet Dry. The Bio Balls had not been tumbled for long, long time. It was a fish only without any Media except for Bio Balls. You need some type of bacteria. Bio Balls were replaced removing excess soupy gravey blocking pores and replaced back in sump.

Where is Mojo talking about Bacteria?
That wealth of knowledge will tell you that you need some source of nitryfying bacteria.

Here is what I did to prevent losses. It was dangerous. It was a fish only tank.

I took 50 gallons of a true 158 gallon tank.
I used 50 gallons of a mature tank from water change.
I used 58 freshly made up saltwater.

Salinity matched all of the above. My concern was always temp and Ph. So I matched temperature.

I removed Bio Balls. I tumbled them in house water in a 5 gallon buckets removing the excess gunk. The bio balls were really bad, we are talking gravey here. I wanted them clean, but not too clean. I wanted a bacteria source. That was only filtration I had for a few days until Mark(skimmerwhisper) could get me a nice skimmer. Maybe I was lucky. I know I have to remove bio balls slowly without upsetting the balance. No live Rock with a new skimmer on a tank that has fish only.

Again, Fish only tank- doing a water change you want some type of nitrifying bacteria without a overload of it. Its a very sensitive system. I would not recommend a 100 percent water change unless you have matched PH and temperature. You may have to do this in a emergency but its really taking a chance if you do things too fast. Just my Two cents!
 
Yeah currently, I have a 24 gallon rubbermaid mixing up 18s. It seems to match currently. Temp and Salinity. But I'm going to let it mix for a few more hours.. This bryosis or hair algae needs to go.. Even though I have to tear down in like 2-3 weeks now.
 
Yeah currently, I have a 24 gallon rubbermaid mixing up 18s. It seems to match currently. Temp and Salinity. But I'm going to let it mix for a few more hours.. This bryosis or hair algae needs to go.. Even though I have to tear down in like 2-3 weeks now.

The niced sized water change should dilute some of the excess nutrients in the water column so should help some (granted you are using ro/di water). Good luck with the algae issues! I've been there and know how it can be a nuicance!!! :rolleyes: :)
 
Where is Mojo talking about Bacteria?
That wealth of knowledge will tell you that you need some source of nitryfying bacteria.
Yea but on an existing set up like that Ed their should be more then enough bacterias on all the surfaces of the tanks, tied up in bacterial goo. So it should be a problem.

Mojo
 
Imo its important to let the salt mix for a greater period of time when mixing that much, so the salt doesn't irritate anything.
 
Imo its important to let the salt mix for a greater period of time when mixing that much, so the salt doesn't irritate anything.

+1

I've read numerous times that you should let the salt mix up for at least 12 hours if not a full 24 hours before using it.

But on the other hand I've also been told that once the water is no longer cloudy( all salt is dissolved), then you may use the mixture right away without waiting any specified period of time.

Personally I always try and let my saltwater mix up for a full 24 hours before use. Just my opinion.

Cheers,
Alex
 
If you are doing a 50%+ WC is there any issues with corals toward the top of the tank being out of the water while draining and re-filling?
 
Corals are ok for a short time unless they are completely dry. Corals usually slime to keep in moisture besides defense mechanism for other corals. Coral slime- another different corals worst nightmare remember that. That is my un expert but little bit of experience so far until proven different oppinion.
 
I am no professional here. But I have done a constant water change. More like a transfusion I guess we can call it. I pre mixed about 150 gallons of water. Let sit made sure all parameters are within tolerance. And slowly drained from one side and filled from the other. I did this process in a little over 3 hours and it worked like a champ. I was told the perfect solution to pollution is dilution.
 
Next question. I was always told that the water column itself did not have the beneficial denitryfying bacteria, it was the glass, sandbed, rockwork, and all other surfaces in the tank that maintained this beneficial bacteria. So I was always under the assumption that as long as the new water matched PH (closely),salinity, and temperature then large water changes are good. That is why people have no issues using UV sterilizers. If the water column was the main source for beneficial bacteria then UV sterilizers would cause havoc on the biological filtration process.
 
During move I have done 50% or larger water changes and the tank typically looks better after.
 
Next question. I was always told that the water column itself did not have the beneficial denitryfying bacteria, it was the glass, sandbed, rockwork, and all other surfaces in the tank that maintained this beneficial bacteria. So I was always under the assumption that as long as the new water matched PH (closely),salinity, and temperature then large water changes are good. That is why people have no issues using UV sterilizers. If the water column was the main source for beneficial bacteria then UV sterilizers would cause havoc on the biological filtration process.


Denitrifying bacteria is found deep within your liverock or to the very bottom layers of a deep sand bed. You won't find denitrifying bacteria on any surfaces as they need conditions void of oxygen and these places are highly oxygenated. As for the water column itself, nothing much beneficial found in there in terms of bacteria which is why the big water changes aren't bad. You will however find some bad stuff in the water column like nitrates etc which is where the dilution comes into affect:)
 
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Ugh.. It's all back again.. I just don't understand it all. Lots of dark green hair. I might just mix up 40gallons of new water and drain the tank t.t and hold the two fish I have in a 10gal for a few days. And redo the sand bed. Can you dip the hair in hydrogen peroxide like you can freshwater hair algae?
 

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