What should I do now?

Hi all, not sure which forum to put this under...
My tank has had some issues as of late. I only had 2 fish - a tomato clown and a coral beauty angel when I was plagued by a MAJOR algae take over. That ended up being that my replacement water was full of phosphates due to my filter having issues. I replaced my filter with a better one and have had no phosphates in my water now. I got a more substantial clean up crew and began a regular regiment of water changes (10 gallon each week) and cleanings in order to rid the tank of the algae. It was/is working as the algae, while still present, is greatly reduced. However, 3 weeks ago after a 10 gal water change, I woke up to find my clown dead. I did some water tests and found that everything looked great. I chalked it up to just old age (he had been in my tank for close to 10 years). I continued water tests and water changes. Water quality looked great - Nitrates, Nitrites, Phosphates all 0 and calcium, ph, carbonate hardness etc looked good. One week I had a small drop in my carbonate hardness, but I corrected that with a little buffer. So, I did a 15 gallon change last night. Cleaned out filters and pumps as well. Today my coral beauty was dead. My skunk cleaner shrimp is MIA as well. At this point I'm wondering if there is something with the algae that may have been released as I was vacuuming or something along those lines. I checked the water and it all seems to be in order - Salinity, Temp, etc. all good. I feel like it has to be something like that as I've done lots of water changes and I don't think it's the water change itself.
In any case I now have a 55 gallon tank with no fish, several crabs, several snails, a pencil urchin, possibly a skunk cleaner shrimp, and a few corals that are struggling to survive with the algae (branching leather, hammer coral and yellow polyps). I'm not sure what to do with the tank. I'm a little uncertain about restocking the fish as I'm not sure what's been killing the last couple. If it is something to do with the algae is just leaving things running without fish (still doing water changes to rid the dead matter) best or would it make more sense to sell the corals to a LFS (assuming they'd buy them) and boil or otherwise clean the rocks and start over?
If I were to "start over", would I need to do something with the crabs and snails as well, or would they be OK with the rocks being removed and then replaced clean? If I started over with the rocks, would it make sense to start over with substrate as well and just make a clean start (cycle it and everything)?
I'm just looking for advice and input on the best next step at this point. ANY advice you have at this point would be great!
Thanks in advance!

 

Is the lack of any response mean it's a lost cause or just no ideas?
I'm really just looking for any advice on what may be the cause of fish death and what would be best for the tank going forward. Any advice would be awesome - don't be shy... )

 

This seems to be a relevant thread.

http://www.3reef.com/forums/algae/c...lgae-off-glass-hurt-your-aquarium-140042.html


If you have the money and time I would start with new.

Can not even speculate as why your older fish died off, could be anything from airborne contaminants to lack of O2 as night (check your pumps if you have not already). Introduction of a new fish or invert that could have brought a pathogen in would be my first guess but you did not include that scenario in your post.

 

It may be time to just hit the reset button and start over and essentially cycle a new tank.

For your current set up, it could be so many things. You're doing a lot of water changes lately. What are you using to measure salinity? Is it reliable and properly calibrated? I was just thinking that if it's off, the rapid changes in salinity may be causing issues.

 

Thank you guys for the input!
Corailline - that post you directed me to was very informative. I also had a couple of the white harder stuff on my glass that I assumed was just some corraline algae on the glass... I did in fact have a couple of my rocks fall off during the last water change. I am also wondering if I in fact have the bryopsis, although I thought that was just a form of hair algae. Would it have any dangers towards fish if it were in fact bryopsis as opposed to typical hair algae?
Toronto guy - I've been doing water changes for many years now, and while I can't guarantee my salinity meter is 100% accurate, I use it to measure both the tank and replacement water and do in fact get them to match. Since it's the same meter, I assume I'm ok there. Would you agree or think there may still be a problem?

If a "reset" is in order, would you guys think I could just boil my rock and use it again? Is there a better way to clean them off for use? I've got some fairly large pieces.

 

I basically let the rock dry out side, hose it down well afterwards, stick it in a container with some flow and let it recycle/cure again.