More progress. The tank is drained and mostly clean.
I've been keeping it running with livestock that I owed to a few friends, trying to get everyone's schedules aligned. That finally happened so Saturday morning the work began. I wish I had taken pictures but I was more concerned with moving the dozen or so fish and 30 or 40 corals that still remained in the system.
Bright and early I shut everything down and started a siphon to drain the water (with a normal garden hose, it takes a good hour and a half or so). Started a second siphon to fill buckets. As it drained I removed the corals and few pieces of rock that were left.
Once it was down to about 6" of water left (so, about 90 gallons!) the real fun began.
I took off my socks and climbed in the tank. With a net in each hand I was able to corner and capture the fish.
The most interesting part was turning over the low, flat rock that my pistol shrimp had been tunneling through and building up daily for almost two years. It's about 18" across and the whole rock is just a maze of tunnels:
Anyways once the livestock was out I drained the rest of the water, scooped out the sand, drained the sump, and called it quits for the day. That was about 6 AM to about 3 PM. And left me with an empty, but dirty tank.
Anyone who has kept marine systems will know my next problem. Coraline algae. Lots of it. And it's not like I can take this tank out to the driveway to hose it out. So I did the next best thing. Brought the hose to the tank.
I've used vinegar and scraping tools in the past but just due to the sheer immensity of this beast I didn't want something that tedious. So I kicked it up a notch and bought some dilute HCL (muriatic acid). I bought a brand marketed as "low odor" which basically means it's sold diluted compared to what you'd typically buy. Of course they charge the same amount. But that's OK with me, because I was going to dilute it anyways and I'd rather buy it already partially diluted vs. full strength and dangerous.
My method of attack was to put about 2" of water into the bottom of the tank to allow for diluting acid as I worked. Then I put a 50:50 mix of the acid and plain water in a spray bottle that could shoot a cohesive stream (instead of anything resembling a mist - I wanted to reduce the amount of acid that was floating in the air). I sprayed down each wall, then went back and scrubbed with a natural bristle brush on a long handle. This worked incredibly well - the coraline just melted, and the brush was more to just push it down into the water rather than having to actually scrub. Other than a few very tenuous spots, it was more or less clean in about an hour.
Then I used the hose to put about 120 gallons into the tank, rinsing everything down, before siphoning it all back out.
So the tank is mostly clean now. As I have been prepping I've been rethinking some of my plans. Earlier I mentioned how I was thinking of converting to an open-top in order to allow emersive growth and potentially some riparium-like plantings. Now, I'm not so sure I want to do that. Mostly because of our cat, who I happen to like almost as much as aquariums. I'm pretty sure she'd be up on top of the tank, reaching into it, every chance she got. She's feisty and (unfortunately, in this case) actually seems to LIKE water, so there's nothing to deter her from making a mess of an open-topped tank. So I'm starting to think I'll have to scrap that whole idea and just leave the structure as-is.
The good news is, that means I can cut several weeks out of the schedule.
More to come...