Lets Talk Substrates for the Marine Aquarium

bostonreefer78 · Feb 4, 2014

given the risk of hydrogen sulfide gases building up in a deep sand bed I have always tried to maintain a healthy balance or aerobic to anaerobic bacteria's in the sand bed by properly grooming the sand bed, I generally try to mix the sand up every week to keep the deep spots from building up toxic gases, it releases trapped waste and allows the filtration and protein skimmer to capture this waste before it has a chance to turn noxious.

J062682l · Feb 6, 2014

Do u guys think that crushed coral can hold in phosphates and nitrates ?

Lockridge49 · Feb 12, 2014

J062682l said:
Do u guys think that crushed coral can hold in phosphates and nitrates ?

I just set up a 8g about a 9 weeks ago and I put crushed coral in it...I have not had any problems yet with my phosphates or nitrates but I always have it in the back of my mind making sure that my levels are staying normal

Paul B · Feb 13, 2014

Originally Posted by J062682l
Do u guys think that crushed coral can hold in phosphates and nitrates ?

I just set up a 8g about a 9 weeks ago and I put crushed coral in it...I have not had any problems yet with my phosphates or nitrates

I put in dolomite 42 years ago and I don't have any test kits so I have no Idea what the nitrates or phosphates are and don't care. Dolomite is similar to crushed coral but different than crushed nuts that you would find on an ice cream sundae.

bsnow0410 · Mar 19, 2014

Anything white on the bottom should help the corals grow because light reflects to the bottom of the corals to give more light penetration all around.

fungia_fiend · Mar 19, 2014

My tanks don't wear pants. I'm completely barebottom now, and have been for awhile. Having said that, I object to the barebottom write up on this post. I don't think its fair.

This lack of substrate is preferred by those hobbyists who prefer a clean, sterile look in their aquarium

This is what people with sand say and it kind of ticks me off. It isn't even remotely sterile. It is, as you state, easier to maintain. But sterile? Are you kidding me? I have all kinds of growth along my bottom from coraline to zoas to tube worms. Sterile? HAH!

While maintenance is easy, it must be done regularly as debris blowing around the tank can be very unattractive.

It really doesn't have to be that frequently. I siphon detritus every couple weeks. Big deal? When I had the SPS only tank, I had so much flow nothing ever settled, and it wasn't just floating around. Good lord. And "unattractive" is more anti-barebottom bias.

The lack of substrate means that the hobbyist is gaining no natural filtering benefit from the substrate

This is either overblown or an outright myth. I have no filtration problems at all from just rock. None.

unable to keep sand-dwelling inverts or sand-sifting fish.

This is overblown with the exception of some very particular sand sifters. I have an aquacultured watchman goby that has never even seen sand. Never. He's perfectly fine. A sand sifting starfish would be a problem, but they'll starve even in a monster DSB. It just takes longer.

Additionally, Extra care must be taken when building rock structures or when working in a BB tank as there is nothing to absorb the impact should a rock wall collapse.

Again, overblown. I've dropped rocks. Plenty. They really don't come crashing down in water anyway. I've never cracked anything from a rock drop, ever. Can it happen? Probably, but I've never seen it and I've dropped LOTS of rocks onto bare bottom. If the tank was empty its a bigger problem.

My rocks always go directly onto my glass. No problems, ever. And if you're really paranoid, its cheap and easy to add starboard to the bottom.

A study conducted on the denitrifying effects of sand beds noted what appeared to be a correlation between substrate depth and aquarium deaths; with death rates up to twice as high in shallow substrate tanks, and a word of caution that "it doesn't get much shallower than bare-bottom." While I've attached a link to the article, I urge caution in reading too much into the study, as this was not the focus of the actual research.

And this is just ridiculous. Plenty of us are keeping plenty of fish in bare bottoms. Most aquaculture facilities use barebottom exclusively in their rearing tanks! This study shouldn't even be brought up in the same paragraph as barebottom. One, it wasn't even a barebottom study. And two, it is completely obvious at this point that we aren't having any problems with fish.

You like sand? Great! Use it! I did for years! I just get tired of correcting BB myths across the various forums. Basically, the moment you use the word "sterile" and "BB" in the same sentence you'll get me riled up.

hart24601 · Mar 21, 2014

I switched to BB too and love it. You can paint the underside of your tank; I used a salt and pepper color - sort of a flake. Looks great and if you want to put sand back in you would never see it! Keep the fuge light from being visible too. I have seen quite a few BB that corals grow over, they are pretty sweet.

FYI our reef chemist Randy Holmes-Farley says that calcium based substrates will not dissolve enough to add any significant stability or calcium to the water, the pH just doesn’t get low enough. I don’t know if I can link to other forums, but a quick google search will show him stating that in many different forums. I don’t have my phd in chemistry from Harvard like he does, so I tend to believe him!

81Shaun · Mar 22, 2014

so what does a person do when 99% of the sand is covered by the lr? ive got about 3 inches around the rock to vacuum. I have a 24 nano with SSB would just going around the rock bottom vacuum be sufficient ? or am I going to have move the rock all the time ?

skinz78 · Mar 23, 2014

I'd just vacuum what you can get to.

SantaMonica · Jun 12, 2014

Another bit of info: Calcite might be considered instead of aragonite, because calcite does not dissolve much at the pH of SW. Thus your sand will not slowly disappear

bairdimusprime · Jun 13, 2014

i kept a shallow sand bed and suffered a huge crash... i switched to Crushed Coral and have had an amazing turn around...
but each tank is different to to each their own

Tempest · Jun 13, 2014

Any substrate you choose will not dissolve enough to have any significant affect on calcium or alkalinity, but it will for sure release trace elements if you use crushed coral or sand made from limestone created by coral. Using crushed shells/calcite doesn't make much sense since the trace elements released are not the same as what corals use to build their skeletons, and you could in theory end up with too much of certain trace elements in the water as they are not used, which could be detrimental to coral health or cause massive algae blooms (iron comes to mind). Also, someone earlier said they mix up their entire DSB to prevent build up of sulfuric gases. That defeats the entire purpose of having a DSB,as you essentially are turning your sand bed into a nutrient trap because neither aerobic nor anaerobic bacteria is being given a chance to grow and consume waste.

Carlson Moncrief · Aug 10, 2014

I used crushed coral for several reasons. 1) its easy to siphon your sand band because all the samf wont get sucked into the bucket. 2) it looks good. 3) it wont cloud your tank near as easily.

REEFDONKEY · Aug 12, 2014

fiji pimk live is my fav

jman9331 · Jan 31, 2015

With a fish only aquarium is it better to have a shallow or deep sand bed?

yazeed · Feb 1, 2015

I dont think deep sand bed is important in any tank,,,whats the idea!!!! Is it amonia factory after a time!!!!
I think all of us try hard to have a cleen tank as possible and thats not gona happen with that,i have 4cm of crushed coral,its easy to clean or desturb,keeping the ph stable.

jhast0n · Feb 1, 2015

set up my first SW and its a BioCube...

Okay so my husband and I have watched alot of online videos!! But, we are kind of stumbling on questions as we are setting this up. 1) the water is somewhat cloudy, I assume this will settle in time, but I what I could have done to not have my water so cloudy? 2) I want this to be a reef tank, and in some of the videos 1/2 say dont use bioballs for reef tank use live rock and sand instead, whats your advice? Okay there were tons of more questions but as soon as I started to type they escaped me. I'll check back and start writing down my questions lol. Thanks in advance!!

Humorosity · May 6, 2015

Ok I am very new. Just got a 90g tank but havent even gotten it cleaned out yet. and it might be a while for I can get it running. Right now I am researching trying to save myself the trouble of making silly mistakes. Also I am trying to get a tentative budget going on what I will need to save to get started. Long story short who prefers SSB and who prefers DSB? Who has tried both and which did you end up prefering and why? I am debating right now which way I should go on this. And I figure it couldn't hurt to ask around and see what you all have done and what has worked for you?