Sand: DSB vs. Plenum

I hear ya! Do your homework so you only have to do it once if you do. Good luck!

 

Thank you for the advice. A big concern was disturbing the lowest layer of sand in the plenum. You know all the horror stories others have posted. I have always been skeptical about the stories since my tank has been up so long without a problem. I feel more positive about the transfer now. Would I still have to cycle a new tank or can I transfer the sand and most water and trust that the fish and coral will be OK? Any additional words of advice before we make this big decision?

 

I think if you remove all on top carefully you should be fine without any problems from your sandbed. Just a hunch. And I think if you transfer most of your sand, water, rock, and any filter material, your fish will be fine. That has worked for me in the past.

 

Soooo Glad I joined 3reef!

This is great advice! I will let you know how it turns out when we decide on the new tank and set it up. I am more inclined to go ahead and do it now and excited about the new possibilities with a larger tank. Thank you.

 

Mat Rogers, Hi, here we go. I took a 200lt tank and placed an eggcrate plyth in a shape which left a gap of 2-3 in around the edge, about 3in up from the base. I put 15-18kg crushed coral as substrate in and around this to a hieght of 2.5in, leaving half in under the eggcrate. On top of this I place 1.2in thick bleached coral slabs, covering the entire top. I then place approx 20kg of bleached coral base rock on top of this. I blacke out the entire tank with a wrap around black bin liner, placed 3x1000lt updraft pumps at the back, and 1x45ooltr crossflow pump at one side, and swicthed it all on. It took 12 days to kick of on ammonia, and 42 days later the nitrite dropped to zero. I put 1xspoonfull of sodium chloride int the tank, and kicked it of again. It took 4xdays to reach zero nitrites again. I did it again, this time it took just 2xdays, I then transfered 20kg of coraline seed rock from my old tank, and took of the binliner after 4xdays. One by one each day, I put one strip of LED lights on end in 4xstrips and 2xnight lights. That was 6xweeks ago, The coraline is spreading nicely, and the original 40-60Nitrate is reducing down to 10-5ppm,with only one main water change after turning the 1st lights on. Phos is nil, and there is no sign of any bad algae, cyno or hair. I'm keeping my parameters as they should be, and recomend this old tested method to everyone. Regards.

 

my question is what builds up at the bottom of the plenum. obviously this removes nitrates. but isn't it still possible to have it start leeching nutrients back out just like a deep sand bed, build up of phosphates or silicates or build up of nitrogen gas.

so would it be safe to assume that you(matt rogers) recommend a remote version of each with a shallow sand bed in display tank. or perhaps a normally capped off pvc pipe extending down into the plenum area, to allow the siphoning of out of the water every few years.

dose any one have any links to plenums that have been set up over 5 years(10 years would awesome if possible)?