Water Change problem

[koireef]

My 80 gal is two years old and thriving. I did a 25 gal water change, which I have always done monthly. For the first time, the corals have reacted badly, closing up, shriveling up, and basically causing a real chemical battle in the tank. All water parameters are ideal, and I have done nothing different than I would normally do.

Suggestions?

 

[sdt5150]

Koi...

a 30% water change/month is pretty significant. i'm assuming that you don't have sps, and that it's your lps that's having the problem, right? i wouldn't recommend such a large change if you have sps. 20% is usually the largest change you want to do on a monthly basis unless something significant has occurred in your reef to merit a larger change. do you have an RO/DI system for your make-up water? if not, it is possible that there might have been a chemical spill somewhere near you, or some other contaminant might have been added to your water supply prior to it reaching your house. try adding carbon and polyfilter and running it for 3 days to see if that helps the situation.

good luck,
Doug

 

[O P Ing]

hi.
I feel that 30% water change is not necessary for a matured tank (2 yrs), unless you have a large bioload and dose chemicals a lot. However, without knowing how you do water change (adjust temp, salinity, etc.), it is difficult to find out why it reacted the way it did.

At any rate, from the description, it sounds like the corals are stressed, and it may or may not have anything to do with water change. Assume that you use good water, and do all the routine procedure of a water change (I am sure you do), there is nothing detrimental about doing a 30% water change, so don't blame yourself. My recommandation is make sure the skimmer are working properly, since there is a lot of organic that it needs to pull out. Good luck.

 

[PatioB]

I have had the same situation occur in the past. Since I have a large tank, I perform 55 gallon water changes at one time. As a result, it takes time for the RO water to be made. I also had some schedule conflicts that delayed the water change. The water I put in was over three weeks old, the SG was off (I mixed it hastily) AND my RO filters needed replacing. All of these variables came together in one water change and I paid a price.

Now, I make the water on Wednesday, mix in the Salt on Friday. I then heat the water to the same temp in the aquarium and insert a power head for thourough mixing over night. I then fine tune the salinty with a precision hydrometer to the exact values in the main tank. If I needed to add a little more salt, then I let the power head mix for a few more hours. If all checks out, then I pump the new water into the system on Saturday afternoon. Since I've been approaching my water changes in this manner, I haven't had any problems.

I don't know if any of this helps, but I hope you have better success in the future.

 

[John Eccles]

I also own an 80 gal tank. It FO though. I do a 10g water change every two weeks, 15 if needed. if i do more....I start kill things (to the tune of 200 bones). my levels stay acceptable for fish.

 

[Minh Nguyen]

Koi...

a 30% water change/month is pretty significant. i'm assuming that you don't have sps, and that it's your lps that's having the problem, right? i wouldn't recommend such a large change if you have sps. 20% is usually the largest .....
Doug

I don't agree to this at all. I routinely do large water change 50% or more in my old tank. Often more than 50%. If your match temperature and salinity, it should be fine. You laso need to age your newly mix water and airated for 24 hr.
I have no problem with doing a 50% water change. It is certaily more feedctive than two 25% water change.
It is hard for me to do large water change now (500+ g system), but I did change 250 g two weeks ago.
Minh Nguyen

 

[danmhippo]

Large water change is not that detrimental to the tank as previously thought. I have made several changes in that magnitude. But I do match salinity, temp, ph and alk up before I make WC that large. My NSW are stored in trash cans with Ph and heater to keep the water moving normally up to 3 weeks at times.

 

[Vixyswillie]

Minh and danmhippo... do you match calcium levels, as well?