Timfish

Just FYI, "old school" is T12s and 5000K MH.  😄

One of the more original names I've heard for a hermit.   ANd keeping the GSP on the sand makes it easy to frag colonies as it grows onto the sand.

Keep adding phosphate, probably best to stay with you current dosing levels.  Even if you aren't seeing it on your test kit your corals are enjoying it and that may be why you don't see it on your test kit.  You might try verifying your tester by adding a drop of neophos to the water sample.  It should give you two results.

To start with I'd be doing weekly water changes (5% - 10%) siphoning off as much algae as I can.  Steel Straws may help maximise reducing the unwantd stuff without going over 20% - 40% monthly total and sand can be rinsed off in fresh nwater or aquarium water and returned. Nuisance algae can dump a lot of DOC into water that promotes microbial issues with corals and you don't have a lot of corals yet to counter by promoting microbial beneficial processes.  As far as "ideal" above .03 mg/l, this was the threshold number identfied by researchers at Southampton University to reduce the risk of phosphorus deficiency.  For refference, upwelling will expose corals to .3 mg/l, one study showed increased growth in Acropora murcata at .5 mg/l, RIchard Ross (Thales on the forums) has sexually reproduced acropora millipora at .9 mg/l. 

     Yeah, good example how an animal can change between systems and why it can be important to  learn as much about how an animal is kept to keep colors

And very beneficial as long as it stays off corals.

Looks good, I'd add a cross piece in the middle top to keep the sides from bowing out.

I'd say it's some kind of sponge.  Just leave everything and wait to see what happens.  It likely won;t grow into the light much more than it has already.  if the parts exposed to light start turning grey then black then I would take it out.

I've got a really big green birdsnest, Seratopora guttatus, for sale.  Colony is roughly 12" in diameter.  $500 Cash or PayPal.

They work great but need a lot of maintenance.  One of my clients really likes them but they've got two sets they swap out for cleaning.

Can they measure how fast that channel is widening then?

Considering how big some of those fish will get your 180 is nicely stocked already.    A blonde naso might be a good addition and I've always liked the Heniochus and Yellow Pyramid Buterfly combo if you're adding more after you get the 180 up and running.  Some wrasses would be good too.

Curious how that channel formed.

The polyps will split just like a cell splitting.  The skeleton and polyp start to elongate, a new mouth forms and over the period of a few months the two mouths seperate and become two seperate polyps.

Heavy duty totes work well but for those reading this I've seen the light duty totes stretch and bow alarming amounts and would advise against using them.

A light duty tote would work cut down and set inside for a sand bed or rubble rock bed.   Potentially, for automated water changes more of the sump volume could be used so thw return pumps would suck air and the sand or rubble would always stay submerged.

I'd guess some cyano like Lungbia or something similar (what I reffer to as "snot" algaes).  As an aside, you definitely need an alkalinity test kit, API is super cheap and easy and when I compared it to two Hanna testers more consistant and as it is about twice as sensitive as the meq/l standard used by many researchers it is more than sensitive enough.  Calcium, pH,magnesium amdPO4 would be helpful too but alkalinity is the one I use frequently.  Use steel straws to siphon it off as frequently as you can but I wouldn't do more than 10% water change at a time.

Have you looked at replacing just the shaft and impellor?  Even the ceramic ones will wear over time.  I don't have any of those pumps but I know the controlable Jebao DC on friend's tanks seemed pretty quiet.

PMed

Personally I don't see a big  difference between a FOWLR and a reef system.  If wild or maricultured live rock is used there's organisms that want the same conditions as corals.  Various coraline algae for example.  There's also corals that do well in lower light so the same selection process would  still applies, decide on lights then get animals that will do well with those lights.   It may not happen on the same time frame as brighter lit systems but there's still the same battle with nuisance algae.  Obviously there can be a big cost savings, both with up front equipment costs and long term costs.   

Just a note on DOCs;  There is a big difference in microbiomes depending on the source,  Algae DOC tends to promote heterotrophic microbial processes which are ineffecient and increae demand on on oxygen.  DOC from corals and coraline algae promote autotrophic microbial processes that are more effecient and can conserve or increase oxygen.  This may be a minor issue but it is worth considering IMO.

I'm a much bigger fan of "islands" for zoas than "gardens"  with several varieties together sooner or later one overgorws the others.  With "islands" it's also easier to get frags from the edges.

Let me know when you're ready to try some more euphyllia.   This time having some amoxicillan or cipro for dips would be handy.  Since we moved stuff between your 40 and one of my frag tanks I'm still thinking the problem I had with the same gold hammer is related sinve it happened at alsmost the same time.  The 5 or 6 polyps that survived after a 2 hour dip with ammoxicilan (~125 mg / 1 gallon) are doing well.

Yup, some kind of sponge.  Gotta love maricultured or wild live rock.  Met an aquarist that has a mantis shrimp in their display for 2 years and no issues.  At feeding time it swims out and takes shrimp from tweezers.

Notice the spoon shaped tips on the claws.

https://www.vox.com/down-to-earth/2023/9/27/23883039/florida-coral-reef-caribbean-king-crabs-restoration

Welcome back!  Looking forward to seeing your system develop!  Be sure to start a thread in the "Build" forum or if you want to continue with your old build thread let me know and I'll unarchive it.  For new additions check out the livestock section of the "For Sale" forum.  fellow members ahve some nice locally grown corals.

Rim's not structural on that particular tank anyway, only reason to resilicone it would be if it's pulled away from the glass.  It has a glass divider and if you look at the corners there's a miter joint.

They are pretty cool and real eye catchers.  From what I've seen in my systems over the years they don't deserve their reputation for catching and killing fish.  They're so slow compared to fish if they're found feeding on a fish they're just doing their job and scavenging and the fish either was dead or on bad shape when they grabbed it.