More Magnetism, and My Father Comes to the Rescue

A couple months ago, I decided to go forward with an idea that I had been contemplating for some time. Until that point, the back wall of the tank above my live rock was relatively barren except for coralline algae- it seemed to be a prime spot for something new, and I thought Aqua-Mags might be the right tool for the job.

I wasn't sure which coral to mount, nor how to mount it, and entertained several ideas before settling on my Green Star Polyps. GSP is a very cheap, very common, and very hardy coral that grows quickly and encrusts over anything, including glass. It will even form a mat across sand. The small colony that I had originally purchased as one of my first specimens had already completely covered the rock that it came on and was trying desperately to find somewhere to continue growing. Many people warn against letting GSP grow unchecked on rock because it multiplies so fast that it becomes a nuisance. I wasn't afraid of handling or cutting up the colony for this project.

Another decision was what, exactly, I would put these polyps on. I settled on some thick branched dead coral skeleton from my LFS. My reasoning was that once the GSP encrusts it would look interesting and provide depth on that side of the tank. I bought four or five fragments of different sizes and shapes and rearranged them until I was satisfied. Using some cyanoacrylate glue and a healthy lump of reef-safe two-part epoxy, I put together the dry liverock over several days and attached one magnet near the base.

Before gluing...

Epoxy drying, piece by piece.

Almost done - just a couple of small pieces left.

Using only one magnet was wishful thinking at best, but I wanted to experiment with how well (or poorly) a single magnet could hold this structure taking into consideration the buoyancy from immersion in saltwater. It was a lot heavier than I anticipated. After fiddling around for a while I concluded that there was no way that one magnet would hold the structure upright on the wall. Another magnet was needed for friction- to provide an additional point of contact that would prevent the whole thing from spinning due to torque from gravity. This introduced the same problem that I had tackled with my first magnet-mounted liverock. The two magnets have to be perfectly flush, their surfaces coplanar, to maximize the hold. Bad news... I didn't do a great job on the second magnet, and it wasn't close to flush. The result was two magnets that did no better a job than a single one because only one at a time was fully pressed against the wall.

All finished, with second magnet. Bummer.

My disappointment with this setback (and lack of precision and foresight on my part) caused me a few days of annoyed brainstorming on how to salvage the project. It certainly wasn't going work work as intended and I had no more magnets to start over. My only recourse seemed to be to saw through the epoxy holding the magnets onto the liverock, break the magnet pair apart, re-epoxy them on a small piece of glass so that they set and dried flush, and then reattach them to my liverock. That seemed like a huge pain in the ass... and it would have been, if it wasn't for my father.

Enter my dad- a precision machinist by trade and overall bad-ass handyman by reputation. He took one look at the piece and mumbled something about one side being "a couple ten-thousandths high". After I explained my solution which involved a Saturday afternoon chock full of sawing and regluing, he thought for a moment and left the room. When he came back he had a large sized piece of almost perfectly flat granite that was lying around in the tool shed and some fine grit sandpaper. Using the sandpaper and the flat surface of the granite, we lapped the plastic surfaces of the Aqua-Mags by maintaining even pressure and slowly grinding the plastic casing in smooth figure eight patterns. After about twenty minutes of this, I gave the magnets a shot on a glass window and they were completely coplanar. The project was saved - I would never have thought of that on my own. Unfortunately I don't have any pictures of the process.

All fixed! Here I am figuring out final placement. Note the Koralia-1 powerhead... Hideous.

Next was the last and probably simplest task of breaking apart my colony of Green Star Polyps. It was actually a tremendous mess; I used pliers to shatter and break apart the dead coral on which the GSP was growing, and discovered several critters living inside. I avoided (purely by luck) touching either of the two bristleworms with my bare hands. The needle-like bristles which line their body can cause irritation if they touch skin. Critters having been returned to the tank, I glued the fragments of GSP all over this structure over the course of a few minutes and left one small portion of it on the original rock to regrow.

Gluing pieces of coral.

After a couple weeks. Not much growth. Also note the replacement to my Koralia-1, a Vortech MP10.

Rampant growth after a couple of months.

One issue this project raised was my Koralia powerhead. I was happy with its performance but it became an eyesore once this coral was in place. I needed something slimmer, more powerful, and way sleeker... a Vortech MP10 fit the bill perfectly! I'm sure I can use the Koralia later on.