New Rock to Established Mixed Reef

[Treefer32]

I've got a 340 gallon display that is 6 ft long, 3 ft wide, and 31" tall with a 75gallon sump, skimmer, algae turf scrubber, matrix rock denitrator (in a cannister filter), and pellet reactor (as a denitrator).

It's been setup for 4 years, and after seeing some other people's tanks in person, I realize I have insufficient rock. Not just for filtration (though that is a motivator in and of itself) but for aesthetics. I've only got rock on the bottom 15" of my display and the top half of the tank is empty. I would like to create some more verticals to my rocks creating more caves and creating more places for corals, and take advantage of the width of my tank as well, by expanding into the back of it more while adding layered height.

Current rocks:
I have currently approximately 130-150 pounds ( at most) and 200 lbs of sand.

With vodka dosing, a reefmat, an algae turf scrubber, a cannister filter filled with matrix rock, I've reached the limits of my filtration. For the last few months now, my phosphates stabilized between .03 and .07 and nitrates between 35 and 39.


Plan: Due to aquascaping an living ecosystem that I wish to enhance, without harming, I plan to add 20-30 lbs of the rock to my sump and add 20-30 lbs (starting the process of restacking rock) to stabilize the next level of rocks.

I've added 10-20lbs in the past without really any cycle issues. The new rock is dry, bleached and acid washed rock, some of it never used, But either way it's been dry for over a year now in storage. Should be pretty clean rock.

What is the max I can add to my sump and display without causing some weird nitrogen cycles? Can I add 100 lbs to my current 150 or so without any negative impacts (other than needing to drain water from the sump due to displacement).

With the high nutrients the bioload is pretty high with around 20 fish, many of them pretty large! (10-12 inches in length.) I feed 8-10 cubes of frozen food a day and 2 sheets of nori per day 4 times a week. (I have one fish that will swallow a half sheet to whole sheet of nori by himself.)

As bacteria colonize the new rock surfaces would they give off ammonia until they're established, and if so, would the other bacteria be able to compensate for it?

 

[brandon429]

you have mentioned phosphate as a motivator, but this step doesn't allow you to control phosphate

you're doing a tank changeup to affect a param you won't be able to alter this way.

you also mentioned limit of filtration: adding more surface area won't address any deficit; your current rock surface area if cut in half would still run your entire setup even if you added five new fish after reducing your rock load. ammonia control is what you get with adding surface area; your ammonia control is fine by orders over.

knowing that, do you still want to proceed? it's easy to add what you like, adding inert surface area doesn't degrade the ability of the current rocks which are far in excess of what you need for permanent ammonia control.

if you want to alter nitrate and phosphate you must do it a different way than adding surface area.

 

[Treefer32]

Filtration may be an excuse. it's more for aesthetics and I'd like homes for more fish. Right now my fish are getting creative in finding their own caves / territory. Providing additional caves and openings where they can live would be a big motivator. Hopefully creating less aggression. I guess I also thought the inside dark crevices of the rocks (if pourous) would provide homes to denitrifying bacteria. May take a while to establish, but 4-6 months from the addition of the new rock would provide more denitrification would it not? Maybe not a ton, but, some? (Don't care about phosphates , they're well within acceptable ranges). Nitrates I'd be happy if they were consistently under 20 ppm without water changes.

 

[brandon429]

hey cool to know. this is the exact breakdown for that use:

your main challenge is the detritus upwell that results, nothing else is a challenge. the rocks you add will either command or emit phosphate into the system but it won't be able to be predicted you'll just have to see what they cause, they won't harm anything. when you remove rocks from this system to change/replace/relocate they leave a detritus trail that will wake like a little cloud in the water. in your size tank the dilution won't kill anything but your % risk includes delayed outbreak of latent fish disease relative to your disease protocol and other variables and there's a decent % chance of a small outbreak of something like cyano or algae that can capitalize when waste stores are redistributed.

I give your approach a 95% chance of doing nothing wrong based on your tank's dilution/a big padding for tank work. you can simply swap, move arrange what you like and the upwelled waste will be handled per your system design. if this was a nano reef I would recommend a rip clean because lacking dilution, waste upwells can kill.

the main benefit to you of updated cycling science is that your current working surface area isn't required, it's a vast overage per the need to handle ammonia in your setup, in any large reef setup using live rock.

old cycling science said if you lost any bacteria they'd have to be replaced, or the system would crash. not true

if you reduce bacteria after reaching your minimum threshold then there's a deficit. no reef tank is near its least possible surface area safety redline. you can mix and match as you see fit. adding to or subtracting from your current rock setup isn't going to affect your main ammonia control, which prevents reef tank's crashing.

detritus upwell is the complete risk, and dilution saves you much concern compared to a nano reefer.

 

[SPR1968]

I’ve added new rocks to both my tanks, without any issues whatsoever, so assuming it’s ‘clean’ I wouldn’t have any concerns.

 

[Treefer32]

hey cool to know. this is the exact breakdown for that use:

your main challenge is the detritus upwell that results, nothing else is a challenge. the rocks you add will either command or emit phosphate into the system but it won't be able to be predicted you'll just have to see what they cause, they won't harm anything. when you remove rocks from this system to change/replace/relocate they leave a detritus trail that will wake like a little cloud in the water. in your size tank the dilution won't kill anything but your % risk includes delayed outbreak of latent fish disease relative to your disease protocol and other variables and there's a decent % chance of a small outbreak of something like cyano or algae that can capitalize when waste stores are redistributed.

I give your approach a 95% chance of doing nothing wrong based on your tank's dilution/a big padding for tank work. you can simply swap, move arrange what you like and the upwelled waste will be handled per your system design. if this was a nano reef I would recommend a rip clean because lacking dilution, waste upwells can kill.

the main benefit to you of updated cycling science is that your current working surface area isn't required, it's a vast overage per the need to handle ammonia in your setup, in any large reef setup using live rock.

old cycling science said if you lost any bacteria they'd have to be replaced, or the system would crash. not true

if you reduce bacteria after reaching your minimum threshold then there's a deficit. no reef tank is near its least possible surface area safety redline. you can mix and match as you see fit. adding to or subtracting from your current rock setup isn't going to affect your main ammonia control, which prevents reef tank's crashing.

detritus upwell is the complete risk, and dilution saves you much concern compared to a nano reefer.

That's great, I agree, some smaller pieces may need to be removed and/or Sumped to arrange for shapes and sizes. As far as the upwell of dormant junk. I agree that's the biggest issue and I'm hopeful that the base rock I have won't need to be touched. It's big bulky rock that was tough to get in place. Relocating the base rock would cause many unpleasant things, including disgusting dust storms of stuff that I don't want to see....

I've got many bristle worms. So, I'm actually more afraid of injuring myself in the rock moving processes. I have no plans to be stabbed by bristle worms!

 

[brandon429]

hey that's a valid mention. in the thread "265 reef" from the disease forum, that poster cut his hand so many times working with large tank live rock he developed severe rashes, infections, bacterial sepsis no joke and went the hospital and we didn't hear from him for a while. there are indeed direct health risks in deep dive large tank work.

 

[Treefer32]

hey that's a valid mention. in the thread "265 reef" from the disease forum, that poster cut his hand so many times working with large tank live rock he developed severe rashes, infections, bacterial sepsis no joke and went the hospital and we didn't hear from him for a while. there are indeed direct health risks in deep dive large tank work.

Ouch! I'm a somewhat of a germiphope. I sterilize my hands before and after feeding or anytime my hands touch the water. I get rashes from washing my hands too much on tank cleaning days. But, agree, blood infections are definitely a real thing and there's sharp calcium based growths on the rocks. So, good point, another reason to wear some gloves when doing this.

I'm excited to have some new homes for corals as well as for fish. I like the fuller rock look. Here's the look now.. Planning to remove some of the large chalace in the center, and the rock forming the tunnel on the right has 80% of my corals on the right side, So, plan to move that rock and stack behind it and maybe even angle it more outward so, rocks can jut up from that cave creating a couple new smaller tunnels across the right side. I like having the front open sand bed for lesser light need corals, but, I could expend out to the front a couple inches as well. creating additional smaller caves around the sand bed. The fish swimming by the glass there is a Creole Anthia that's 10-12" inches in length. He has teeth as well... Behind him you can see the female that's following him. She's half his size. Had both as a pair. A reef buddy got them from Petco and treated them with copper for 60 days for me. The toadstool on the bottom left is not quite dead, not quite alive. Not sure what to do with it yet. May replace it with rocks. Heh.

 

[brandon429]

hey that's neat/rare among large tanks. you have some of the lowest degree of live rock we usually see, that would be close to a negative aquascape if you didn't have sand. I must admit that tank is perfect as is I wouldn't change that arch much, it's allowing flow-through and lower catchment % of waste than huge rock wall stacks like years ago we'd see in all scapes/

 

[Treefer32]

Yeah I was going for a more simplistic look. My fish love the two tunnels. My tangs especially fight over them. I have an MP 40 behind both tunnels that the Tangs love swimming against every day. They just swim into the tunnel and swim against the MP 40. They'll fight for turns in both tunnels and if one of the three tangs gets kicked out, then it goes and fights for the other tunnel. It's hilarious to watch fish fighting over their treadmills. It's like hamster wheels. I placed the MP40s their just to get debris from the back of the tank to the front so the Gyres can recirculate it into the overflows. I had no idea fish would love the MP40s as much as they do!