Coral appearance before and after water changes

[Waters]

The day of my water changes (after the change), a lot of my coral (specifically Hammers and Wellso) expand almost 1/3 bigger than they are throughout the entire week. I don't really notice too much of a change with any of the SPS or softies...it is mainly LPS. I have been trying to figure out what the addition of 8 gallons of new saltwater (to a 60 gallon reef with a 20 gallon sump) has that is making the coral respond like they are. I have done before and after tests of SG, PH, Alk, Ca, Nitrates, Phosphates, and Magnesium with the figures not changing after the water change. Is it the trace elements? What can I dose to keep the coral at full expansion throughout the week? I want the tank to look as healthy all week as it does on water change day.

 

[Macdaddynick1]

Chemical warfare?

 

[Bassett22]

addition of other trace elements that you don't test for? iodine, strontium, etc.

 

[4FordFamily]

Mine are angry for the rest of the day and look fine the following day.

 

[Waters]

addition of other trace elements that you don't test for? iodine, strontium, etc.

That is what I am leaning towards....I guess I need to find something that contains those elements that I can dose to verify that is what is missing throughout the week.

macdaddynick1 - I don't think it is chemical warfare....I do run carbon 24X7. I only have 2 small softies.....the majority of the tank are LPS and SPS with nothing really in danger of reaching out and attacking.

 

[hart24601]

Before you start dosing anything to try and keep them looking like they do after a waterchange, remember they might be expanding because they are stressed and not happy. I have noticed that some LPS expand or contract when they are stressed, not saying that is the case here, but I wouldn't automatically assume they are doing better after the WC. Do you run activated carbon in the tank? You dose anything in the tank at all, 2 part? Do you spot feed the LPS?

EDIT: I see you run carbon, posted it as I was typing!

 

[Waters]

Before you start dosing anything to try and keep them looking like they do after a waterchange, remember they might be expanding because they are stressed and not happy. I have noticed that some LPS expand or contract when they are stressed, not saying that is the case here, but I wouldn't automatically assume they are doing better after the WC. Do you run activated carbon in the tank? You dose anything in the tank at all, 2 part? Do you spot feed the LPS?

EDIT: I see you run carbon, posted it as I was typing!

Yes, I just starting dosing 2 part within the last month...my Alk was running consistently between 7-8 prior to dosing so I am dosing enough Alk and Ca to just keep it around 8.5. My Ca has never been an issue always hovering around 450. I do spot feed the LPS roughly once a week but the change definitely happens within 1 hour of doing the water changes (which I do once a week). I guess it is possible he is stressed but I always assumed they would shrink rather than inflate if they were bothered.

 

[hart24601]

Perhaps stressed is too strong of a word here, but they just might be reacting to a small change in the system. Not necessarily good or bad, but just a slight change is enough to bring that response be it a feeding or an otherwise different reaction. Just keep that in mind before getting concerned with dosing or trying to see that response all the time! Maybe the system is lacking in something and you will be able to keep that effect you are seeing, but I just want to put that thought forward before you start chasing the "missing link".