Changing live sand

likwid · #1 02-21-2009, 07:12 PM

Hey guys,

I have a 28 NanoCube HQI that has been set up for about 8 months now. Everything is going great and I have never had any problems with algae or anything. The only mistake I made was using crushed coral as my substrate. I would like to replace this with a very fine white live sand. How hard would this be to do, what is the best way to do it, and what are the repercussions of swapping out substrate?

Thanks

Myka · #2 02-21-2009, 10:07 PM

Crushed coral is a bit harder to swap out than sand, but it's doable. By chance, is it fine enough that you can siphon it out? If so, you are lucky, and you can simply just siphon out a 1/8th section of the cc. If not, then what you need to do is turn off all the pumps and use a gravel vacuum and clean a 1/8th section of the cc really well. Then use some sort of scoop (I would use a noodle scoop with holes in it so the water will drain) to scoop out the section that you cleaned really well. Then use a scoop (with no holes) to gently lower the sand to the bottom, and gently pour each scoop into the area where you took the cc out. Move really slowly when you are scooping out and scooping in to disturb as little as possible, but your tank will definately be cloudy. Your tank may remain cloudy for the entire time it takes to swap over, and maybe even a week after that. Turn the skimmer back on as soon as you are done, but wait a couple hours before you turn the powerheads back on. Do 1/8th of the cc twice per week so that it will take 4 weeks to complete. If you do it too fast your tank will spike ammonia and crash.

likwid · #3 02-22-2009, 12:54 AM

Thanks Myka. I only have about an inch of substrate in most areas. Could I just syphon out the sand and leave about 1/4" and then just put the new sand on top, using the technique you described?

chandigz · #4 02-22-2009, 01:24 AM

Rather than leaving a 1/4 " of crushed coral and covering it, it would be better to do a section at a time. That way you are less likely to start a new cycle. If you do it this way, the old crushed coral will help seed your new sand. If you cover the crushed coral you will kill anything benifitial on it. You will also find that the crushed coral will work its way to the surface of the sand over time. I find that most bagged live sand is fairly clean and doesn't cloud the water to much if added carefully. I use a cylander like a gravel vac, fill it with sand and lower it into the water with my hand over the bottom and then let it slowly slide out the tube. good luck!

likwid · #5 02-22-2009, 02:50 AM

I should have mentioned this before, but I plan on leaving about 40% of the current substrate in the tank. All of the substrate under and close to the live rock will remain. My rock is all piled up in the back-center of my tank, so I would be replacing the entire amount of substrate in the front of the tank and the sides. By doing it this way, am I able to take out larger portions at a time each week?

Myka · #6 02-22-2009, 02:40 PM

Quote:

Originally Posted by likwid

I should have mentioned this before, but I plan on leaving about 40% of the current substrate in the tank. All of the substrate under and close to the live rock will remain. My rock is all piled up in the back-center of my tank, so I would be replacing the entire amount of substrate in the front of the tank and the sides. By doing it this way, am I able to take out larger portions at a time each week?

Not unless you want to risk a tank crash. Why do you not want to change all your substrate? The less cc the better.