When to do water changes

pwrboat

New Member
I need a non LFS answer to when to start and how often to do water changes ?, and also how does one know when a water change is needed?, what parameters to look at.
I have a 300g FO tank thats been running for 9 months. no live rock, about 3" of sand, 2 proclear 40g wet dry's, a large proclear skimmer and a turbo twist 36watt uv filter.
The fish are 4 perculas, 2 yellow tangs, 1 archilles tang, 2 dragon gobies, 2 dwarf angels, 3 pj cardinals, 1 hippo tang and a lunare wrasse. Today I purchased another hippo 6 green chromis and a flame hawk. alltogether 24 fish about 1-2" the largest being the archilles tang about 3".
I just checked my water ammonia 0, PH 8.2, ni 0, na 0. from those readings i gather the water is fine, is there other tests i should run?, how do i know if a water change is needed? :notsure: .
p.s. I only add RO water.
 

mcsd22

Member
I think you will find alot of different answers but I do 10%every 2 weeks. I really don't see any rise ain levels but I do it so I don't have problems. I might be doing it to often but better safe than sorry. I do think if you just put 8 fish in at one time you are going to see some rise in your levels. Even 300 gallon cant adjust to that big ov a bio-load change. Why no live rock?
 

moby

Member
WOW!
9 months running with fish and no nitrates!
JMO, but I would make sure your test kit works just to be safe.
Moby
 

birdy

Active Member
I would be very very suprised if you actually had 0 nitrates in a fish only tank with such a load of fish. Might want to double check that test.
Ideally a 10% water change every week is recommended.
Most people do a 10-25% water change a couple times a month. Some people never do a water change at all.
Unless something is desperately wrong with your tank you are not going to have "gauge" on when a water change is necessary.
It is sort of like a oil change on a car, you want to change it regularly so problems do not occur.
 

omgsaltwat

Member
Originally Posted by Birdy
I would be very very suprised if you actually had 0 nitrates in a fish only tank with such a load of fish. Might want to double check that test.
Ideally a 10% water change every week is recommended.
Most people do a 10-25% water change a couple times a month. Some people never do a water change at all.
Unless something is desperately wrong with your tank you are not going to have "gauge" on when a water change is necessary.
It is sort of like a oil change on a car, you want to change it regularly so problems do not occur.
I agree.....Do you have any pics of your tank and fish? I would love to see it
 

reefnut

Active Member
The water readings that one gets should not effect their water change schedule unless they are showing a problem. Otherwise a regular routine should be followed... I like Birdy's comment about a oil change in cars... water changes is a pro-active method of avoiding problems.
 

pwrboat

New Member
Originally Posted by mcsd22
I think you will find alot of different answers but I do 10%every 2 weeks. I really don't see any rise ain levels but I do it so I don't have problems. I might be doing it to often but better safe than sorry. I do think if you just put 8 fish in at one time you are going to see some rise in your levels. Even 300 gallon cant adjust to that big ov a bio-load change. Why no live rock?
i havent put the 8 fish in yet, they just went into the qt tank and i will intro them slowly a few at a time.
i just tested again and 0 nitrates, pretty much the same since after the cycle.
 

pwrboat

New Member
Birdy said:
I would be very very suprised if you actually had 0 nitrates in a fish only tank with such a load of fish. Might want to double check that test.
double checked and 0 all around, is 16 small fish really alot of a load for that amount of volume with all that filtration? could i be over filtering?
 

mcsd22

Member
I dont think you are over filtering and are fine with the new fish. My only concern would be adding them all at once and creating some Am. before the tank could catch up. I would keep an eye on the QT so it doesn't get overloaded.
 

arsen_36

Member
sounds like a nice tank! lets see some pics if you can. by the way get yourself some live rock
for that "Extra" filtration. do a 30g water change every friday or something. it's not so bad....
 
S

sinner's girl

Guest
It is sort of like a oil change on a car, you want to change it regularly so problems do not occur.
Ditto, weekly would be a lot with a 300gl tank. I'd do every two week, and maybe only 10-15%, unless you have a problem or your nitrate start to climb.
i just tested again and 0 nitrates, pretty much the same since after the cycle.
I think they meant to test with a different test kit. I always have lfs or ***** test water also.
If you don't have lr, what do you use for the fish to hide/sleep/play in?
 

moby

Member
Great tank!

9 months running with fish and no nitrates!
My earlier comments weren't meant to be sarcastic, but I would be concerned the test kit was bad.
JMO, I would take a sample of water to a trusted LFS and have them double check the nitrates for you. :thinking:
Moby
 

puffer32

Active Member
Your levels might be right on, with a tank that size and only 8 fish, I would think your levels would be good. You have 8 more fish in QT right now? I would all them slowly, maybe 2 at a time over the next month or so. I would also add some LR, you can mix it in with the decor you already have and it won't change the looks to much, good luck!
 

pwrboat

New Member
Originally Posted by Birdy
puffer he has 24 fish in the tank, most of them small but 24 fish is still a lot.

correction: i have 16 fish in the tank and 8 in qt which will be introed slowly over a month or so
i will take water to lfs this afternoon to check my results
 

birdy

Active Member
sorry I read this
The fish are 4 perculas, 2 yellow tangs, 1 archilles tang, 2 dragon gobies, 2 dwarf angels, 3 pj cardinals, 1 hippo tang and a lunare wrasse. Today I purchased another hippo 6 green chromis and a flame hawk. alltogether 24 fish about 1-2" the largest being the archilles tang about 3".
 

puffer32

Active Member
But some of these fish get really big. Not sure i would put another hippo in there. You would be ok for awhile, but eventually those bigger fish will be overcrowded.
 
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