Catherine, sorry for all the crap your getting with the tank... Well Im going say something and don't take to heart. why not slow down a bit. really thou if seems that your rushing to get this tank up and running really fast here, stocking the tnak with clams and tangs and this..... know your passion for the live stock. May be it time to just sit back and do a life check here.... I'm just giving you my opinion that is all.. Just seems you are running in to major negetivity here since the crashes... time to take a look on why..

I hope you get it all sorted out since you have a passion for clams and SPS

Hopefully nothing too major. I can offer tank space if, heaven forbid, you need it.

I think my salt went bad. I think something settled to the bottom of the salt itself. I usually shake buckets up before we use them, and I think maybe this one escaped the salt shake/mix.

I opened a new mixed bucket, did a WC, and have left the MHs on a little longer then usual right now; they were on for 8.5 hours today. Clams seem better.

you think that you got one of those high ALK bucket that wiped out alot of peoples tanks

Hahaha high Alk, would probably show up as normal alk. levels in my tank. I swear its the clams that bring my dKH levels down so low all the time.

The offender was a bucket of IO salt that we've had for a long while, we somehow managed to have three buckets going at once, and have finally gotten to this one. I bet we've had this salt since probably the summer.

Summer doesn't seem like that long ago for salt to go bad, but as you said when packed it may have settled different. Like you I like to mix my bucket of salt to make sure everything is well spread.

Aw geez, sorry to hear. Hopefully they'll look better in a day or so. Sometimes they just seem to sulk if there's something a little off... hope it's just an off day in this case..

I would step back from the 500g+ tank idea for awhile, and get your 180 to where it is more stress free. of course you cannot control bad salt mixes, but maybe try to improve some little things.
for instance why not use an algae clip instead of the PVC pipe thing?
Also if you had a few less clams, maybe wouldn't have a big of a problem with dKH? (realizing this is like asking the sun not to shine, but JMO)

Too much ambition in this hobby can be a bad thing.

I usually don't keep salt around longer then 3 months, so for us having a bucket that long is quite old. It definitely wasn't mixed because the texture was different right at the very bottom apprently, but it never triggered any flags at the time. Most of the clams seemed better last night after the WC. There were two who hadn't quite come around yet, but hopefully today they will have improved.

Algae clip still causes the same problem. The more aggressive feeders take all the food. A longer PVC pipe like I was using before allows me to spread the food over more space allowing all the fish, aggressive, or not, to get in and eat. Its all about surface area in this case, the more you have, the easyier it is.

Anyone know what kind of table saw blade you would need for acrylic cutting?

Just asked the same question....the more teeth the better...we got a really good one at Canadian Tire, I think it was 80 teeth...but they are costly! $90.00...but works sooooo very well!