To water change, or not to water change

[jdiver]

I have read different opinions on whether or not it is beneficial and necessary to do a water change during the cycle. Some people say you should definitely do a water change during the cycle, and others say you shouldn't. What are the opinions of those on this site?

[eferna]

I would do a water change after the cycle is completed. I usually do only tops offs now.

[HuBu]

well the reason for a cycle is to get an ammonia build up in your tank thru waste, then letting the bacteria within the tank wipe out all the ammonia. its like a test to see if your tank is reef ready, or are the bio filter there. change your water would deplete the ammonia, and that would just mess up the cycle. well this is just my opinion. definitely need to top off tho.

[jdiver]

I agree about not doing a water change during the cycle, but a couple of suppliers of saltwater fish and critters have instructions to do a partial water change during the cycle. It didn't make sense to me, but hey, what do I know?

[lizbeth]

Well I'm going to the other side of the fence on this one. I didn't do water changes in the 5.5 the reading were off the chart. It's taking along time to see critters in the tankand sandbed.

On the rock/tank I'm cycling now I've done water changes to keep the readings from skyrocketing. Plus I rinsed and scrubbed dead off the rock. I see life in the tank I've never seen in the 5.5. It may take a little longer tho' it seems to be coming along ok.

I'll let you know how the experiment goes in a few weeks.

[flaunt]

maybe the answer to this question depends on how much ammonia is produced by the die-off on the live rock.  i did partial water changes because i had uncured rock that really, really spiked the ammonia.  you want some ammonia in there to get the cycle going, but if you have a very high amount, then you'll probably end up killing off a lot more life that would have survived if you had diluted the ammonia a bit...

[Sahin]

I agree with flaunt. You need to balance out a level where you are just doing a few little water changes to not reduce the ammonia/nitrite levels too much, but reduce enough so that the critters still living have a chance to survive.

[JROC]

I think Sahin and flaunt are dead-on. There can be no benefit to letting negative elements build up to very high levels. Just have pateince and do warter changes to keep the negative elements down to reasonable levels. I think it is better to take your time and let what is alive stay alive, rather than give your bacteria a boost and kill other beneficial rock and sand inhabitants.

[printerdown01]

I would recommend small water changes. Approx 10% every two weeks or 5% every week. Normally I have a long explanation as to why I recommend one thing or another. And normally I post as many benefits and drawbacks of both sides (or the benefits of the side being ignored), but all I have to say here is this seems to work best for me! -I'm sorry for having so little explanation... If it means anything to anyone, I managed to keep a damaged SPS (came on my LR and was seriously damaged in shipping) alive during my tank cycle, using less than 10% weekly water changes...  There is no logic to this one, only observation...

 

**oh oh, just though of this... Your LR has stuff on it (sponges, tiny corals, clams, muscles, worms, ect) these things will use up nutrients in the tank. These nutrients will need to be replaced as they use them. Not to mention that the high ammonia levels will be toxic and cause things much stress... Do NOT try to eliminate these high levels (you need them for the cycle), but there is no reason to exacerbate the situation and cause more problems than necessary.

 

 

(Edited by printerdown01 at 5:41 pm on June 6, 2002)

[jdiver]

My ammonia levels were pretty high (7-8), so at the suggestion of several people, I did a small water change of about 3/4 gallon (10%). I just tested again an hour or so after the water change, and the ammonia is at 4, the nitrites are at 4, and the nitrates are at about 15. Thanks for the responses and advice.