sand over crushed coral - can it be done?

[BCReefer]

I’ve been looking at lot of ref tanks, either through the net or on person and I kinda like the sandy bottom. The only problem is that I am using crushed coral for the base. Am I able to put down sand on top of it?

I was thinking of getting live sand, washing it (I think??) and slowly scooping it in over a period of a few days. Would this cause a major spike in my parameters?

I have no major reason other than the look.

Thanks
Patrick

[Aquattro]

Patrick, when I converted my 45g to a reef, I siphoned out the gravel 1/3 at a time and replaced it with sand. I waited 2 weeks between sections and six weeks later I had a complete sand bottom and no cycle. I was a relatively simple process. I think putting sand over crushed coral might create a detritus trap which would be bad. Maybe check with Ron Shimek at reef central.

[canadawest]

Patrick, I can offer a contrary opinion. Due to questionable advice and my lack of knowledge early on, I also started my tank with a 1"-2" layer of crushed coral. Granted I got really fine crushed coral, but it's still crushed coral.

I have since added a bag of Caribsea special grade sand, and about 10lbs of dolomite sand over the past year with no consequence. Now I have a mixed sandbed of several different grain sizes which is exactly what Shimek prescribes.

Unless you are using the coarser crushed coral, I see no reason why you should have to remove it all before adding a finer grade sand. The benefit of starting with crushed coral is that the finer grains will eventually work themselves down through the crushed coral without any stiring required and help to achieve the mixed grains that shimek recommends.

And as a side note, I have never had over 5ppm of Nitrates in my tank since the original cycle. With the proper cleanup crew, there is no reason the sand should become a detritus trap, and even though I only have about a 2" sandbed in my tank, I frequently observe nitrogen bubbles escaping.

[CHEAPREEF]

I agree with Andrew, i also have a layer of CC in wiht the sugar fine sand with no ill effects. My nitrates are 0 after 3 months and dido on the nitrogen bubbles.

Clinton