Great build thread. I am in the process of setting my 150 gallon tank. Just recently build my 70 gallon sump. Follow Marc's web site to build one. Now I am at the stage of designing the aquascape until I saw you curing your Marco rocks. Question, after the 6 hour vingear/ water bath. Did you cover the rocks to start cycling them? You cycle the rocks till your water test were zero, is this correct?
After the vinegar I rinsed them real well with tap water to wash away as much vinegar as possible. As you soak them in vinegar you will see the rocks fizzing, almost like putting an Alka-Selzer in water. The fizzing is the acetic acid in vinegar dissolving the calcium carbonate of the rock and releasing co2.
You want to stop that otherwise the rock "corrosion" will continue.
I then put them on a large vat with freshly made salt water. I did not bring salinity all the way to 1.025. I did something like 1.021 to save some salt.
I did not know if there are enough decaying organic on the rocks to start a cycle at this point. So I threw in a couple of large frozen shrimps.
I also put in 2 maxijet 1200 for circulation and the protein skimmer.
I would suggest against dosing vodka or sugar at this point. People who have done that suffered large bacteria blooms and horrible smell and die off from these rocks.
The rocks went to a slow cycle due to the low bioload. Ammonia went up a little bit and then returned to 0
After a week or so I started measuring about 0.01-0.03 of PO4 so I set up the GFO reactor that I was planning to put anyway on my display tank ( I used the bulk reef supply one which is cheap and so far has been working well for me). PO4 went back to 0 and stayed there.
At this point I continued building the display and just check on the rocks from time to time.
The skimmer was pulling out a good amount of dark grey pasty material that did not smell bad like usual skimmate. I believe it was residual ca carbonate dissolved by the vinegar. Perhaps the skimmer was an important part of the process. I am not sure. It kept the water clean.
I did only 1 30% water change at about 2 1/2 week.
I did not put them in the dark. They were in the garage away from direct sunlight but definitely in the light.
I cooked them for about 5 weeks. By the time I needed them to set up the tank the water had 0 ammonia nitrite nitrate and phosphate. They had a very very light layer of diatoms as i took them out, which I brushed off and rinsed in sw prior to putting them in the display.
The process has worked well for me. Marco rocks are beautifull, very light and are quickly becoming 'live' in the display tank.
Also I did something similar for the sand. I got aragonite sand from ebay. I do not recollect the vendor. There you have to pay attention because most of the sand on ebay is silica sand and not aragonite. This specific vendor had aragonite at a good price.
I cured the sand similarly to the rocks in a separate vat. Only shrimp and a powerhead.
I did all this in the summer with outside temp ~ 80 so I did not worry placing heaters anywhere.
Good luck with your build and link your thread here. I'd love to follow along.
