How muck rock?

[Willbiker]

Hi all.

I have set up a 600 litre tank and have 25kg of marco rock in it with a 1.5 inch sand bed. Do I have enough biological surface area to stock to a medium level ?( fish, corals and invertebrates)

I am currently building a 180 litre sump where I plan to house a skimmer and refugium. I could add media or more rock in here but want to use most of the space for a refugium.

I love the minimal look of the tank but fear i have too little bio surface area? What do you think?

Here is my tank. Still unfinished and lots to do!

 

[El_Guapo13]

Can we get a few more pics from other angels? In particular, from the long side, and one from the front/short side? That way we can get better ideas of all the free space.

Also personally, I think it looks good. Whether or not it has enough for adequate biofiltration... I am not sure. But if you have a refugium setup and mechanical filtration, I would think you would plenty to take care of any bioload... at least until you go crazy and overfill the tank with fish

 

[El_Guapo13]

Can we get a few more pics from other angels? In particular, from the long side, and one from the front/short side? That way we can get better ideas of all the free space.

Also personally, I think it looks good. Whether or not it has enough for adequate biofiltration... I am not sure. But if you have a refugium setup and mechanical filtration, I would think you would plenty to take care of any bioload... at least until you go crazy and overfill the tank with fish

That said, general rule of thumb is 1 to 2 lbs per gallon, or 1kg per 10 liters. So based off of that general rule, at 600 liters you should have 60kg of rock. That said, I do not think I have 29 to 58 lbs of rock in my 29 gallon tank. I could always be wrong though, but I do not remember buying that much rock. I think I might have 20lbs. Maybe 25lbs, because I have some smaller pieces in the chambers of my AIO. Maybe lol

 

[New&no clue]

You might also want to think about what you plan to put into the tank, fish and corals. Do you have have enough rock for them?

 

[TheDuude]

I like the look of your minimalist scape and my tanks tend to share a similar design. Agree with the general rule but keep in mind how much biological filtration you need is based on the bioload of the tank. If you're going to run a high bioload you can always supplement your rock with bio media like the Xport bricks or Matrix. I run matrix in a reactor with very low flow and feel it helps supplement my minimal amount of rock.

 

[Auquanut]

I think it looks really good. The pound per gallon rule is a very murky guidline. That being said, I would suggest looking down the road. Will I have enough surface area for the corals I want? Am I going to stock heavy or light with fish? Will I have enough biofiltration for my intended bioload? Just something to consider.

 

[Willbiker]

Here is a side shot. Ignore the terrible wiring...that's next on the list!

 

[Willbiker]

Thanks for the replies. I would like to utilise my sump to the max so I can keep the tank minimal. I will take a look Into the suggested media from theduude!

How much media can you out into a refugium...would 2/3 full of rock or media be ok leaving 1/3 for chaeto? How much media can I get away with in my sump?

 

[TheDuude]

IMO you cannot have too much biological media. If you have more than what is needed the bacteria in your tank will just not populate it all. Your tanks bioload will determine how much surface area the bacteria will colonize.

In my experience, the bio medias are very efficient if you keep them clean so I would go for a large fuge and try running bio-media in a reactor or between sump baffles.

My fav is in a reactor so during a water change I can crank up the flow and flush detritus out of the media.

 

[Willbiker]

Interesting!

Brightwell Xport Bio Brick - Marine Aquatics Ltd.

Ultra-porous Biological Brick Media with Superior Performance Characteristics Overview Highest porosity and largest useable surface area, per unit weight or volume, of all filtration media available anywhere Provides huge amounts of aerobic and anaerobic surface area for efficient bacterial...

marineaquatics.co.uk

This xport brick claims 1x 9" brick is good for 3800 litres!! What!

For the price of this brick..I could buy 11kg of Marko rock. What would provide the most bio filtration??

 

[TheDuude]

Impossible to determine that - Depends on what you are wanting to do with your rockwork

 

[waleedreef]

That said, general rule of thumb is 1 to 2 lbs per gallon, or 1kg per 10 liters. So based off of that general rule, at 600 liters you should have 60kg of rock. That said, I do not think I have 29 to 58 lbs of rock in my 29 gallon tank. I could always be wrong though, but I do not remember buying that much rock. I think I might have 20lbs. Maybe 25lbs, because I have some smaller pieces in the chambers of my AIO. Maybe lol

that's what written in books 1 lb per 1 gallon or 1/2 - 1/3 of tank volume. but i was wondering frag tanks without rocks and coral/small number of fish are thriving? why this guide doesn't work on frag tank?

 

[Willbiker]

If I threw 11kg of broken marco rock in the sump or added 11 more kg to my tank stacked like it is in the pictures do you think this would provide me with more surface area for bacteria than one of these x bricks. I'm wondering if a couple of these bricks within baffles in my sump, would give me ample bio capacity for an average population of life and will allow me to stay minimal in the tank.

 

[TheDuude]

If I threw 11kg of broken marco rock in the sump or added 11 more kg to my tank stacked like it is in the pictures do you think this would provide me with more surface area for bacteria than one of these x bricks. I'm wondering if a couple of these bricks within baffles in my sump, would give me ample bio capacity for an average population of life and will allow me to stay minimal in the tank.

Crushed LR in the sump will need to be cleaned often to keep detritus from building up. I would worry about this cutting into my cocktail hour(s).

 

[mcshams]

Already stated, but your fuge can run the excess bacteria condominiums with bioblock as @Willbiker linked. That way you can keep your scape the way you prefer it. And through the infinite wisdom of others in this post, really will be determined by your OVERALL bioload you decide to put in the tank (fish, feeding, etc).

In the fuge, there is a 'limit' to the overall effective depth that the chaeto works with due to light penetration, so don't fee as though you need the ENTIRE depth of the fuge for your chaeto (or similar macroalgae)

Tank looks AWESOME btw.

 

[jda]

For bio filtration, the sand that you have will do all that you need, assuming that you mostly leave it alone and don't let it blow all over the place.

There are two considerations with the rock. First, you being happy - only you can decide this. Second, the fish will feel more secure and safe with places where they can go and hid - I am not talking about some caves and crevices that we create, but a pile of rock where they can disappear. I would try and balance this some.

 

[Willbiker]

Thanks ! Good to hear.

In response to JDA, I have an extra bag of sand left over. Would this do well in the refugium?

 

[TheDuude]

I personally am not a fan of sand in the refugium. I keep only Macro algae in my fuge making it easy to pull out an clean all detritus. Again this is just my preference as I like to keep maintenance as simple as possible. That way I have a higher chance of doing it on a regular basis. Sand in the fuge would need to be vacuumed on a reg basis

 

[Heart of Dixie]

I have about 55 to 60 pounds of Pukani rock and a 1-½” sandbed in a 150 with a medium bio-load . The sump has good skimmer and a 20 gallon refugium full of chaeto.No filter socks or GFO, heavy feeding and I dose N03 & P04 to keep it from dropping to zero.

 

[NS Mike D]

A coral grower/seller near me gave me a tour of his set up, DTs frag tanks sumps etc. His system uses only enough live rock in the display tank to mount his corals and give the fish nooks, crannies and arches for the fish to explore and hide. He uses marine pure blocks (you can use anything similar) in his sump and replaces them as needed, ie the second they start to crumble. His theory is that unlike a natural reef that is constantly building new porous rock, in our tanks the live rock and the marine pure eventually get clogged with detritus and other particulate and this lose their effectiveness. Thus, by using the blocks to be the work horse of his filtration he can swap old block for new ones on a staggered basis. Plus it leaves less open rock for algae to settle on.
Pretty interesting