Amphiprion1's 25g seagrass cube REDUX

[Amphiprion1]

First, some current specs and ideas/theories/explanations behind this tank.

 

• Specs:
  
• 25g AGA cube 18x18x18
  
• 14g custom sump 17x17x12
  
• HOB 300 gph overflow
  
• Vortech MP40w ES @ ~80% on Long Pulse Mode to create a rocking effect of an extended wave
  
• Tunze NanoStream 6025
  
• 250w mogul Hamilton Cayman Sun w/ XM 10000K on 8.5 hr photoperiod; approx. 8" from surface
  
• 300 gph return via Tunze Silence pump
  
• 100w heater
  
• Manually dosed homemade 2 part additive added every 2 days
   
  Average Parameters
  
• Temperature: 81-85 Fahrenheit
  
• Salinity: 35-36 ppt
  
• Alkalinity: ~8 dKH
  
• Calcium: ~400 ppm
  
• Nitrate: Undetectable
  
• Phosphate: ~0.02-0.04 ppm
   
  Maintenance:
  
• Very occasional water change, usually after harvesting grasses, which stirs up substantial detritus and releases nutrient-rich porewater. This amounts to about 30% every few months or so.
  
• Activated lignite carbon employed continuously and replaced roughly every 3 weeks to reduce yellowing from decaying grass leaves.
  
• Granular FeO(OH) used when substrate is disturbed, along with or in place of above water change.
  
• Monthly to bi-monthly harvest of grasses, rhizome and all.
  
• Grass leaves plucked every 3 weeks or so to thin vegetation, improve vigor, and allow for better water motion through the plants.
  
• Occasionally add KNO₃ or Ca(NO₃)₂ when phosphate levels rise
   
  Livestock:
  Fish:
   
  
• 2 Amphiprion ocellaris (female approx. 12 years in captivity)
  
• 1 "tribal" blenny
   
  Plants:
   
  
• Halophila decipiens (oar grass)
  
• Halodule beaudettei (shoal grass)
  
• Thalassia testudinum (turtle grass)
  
• Syringodium filiforme (manatee grass)
  

 

After a long string of some bad luck and equipment failures, as well as after having very good luck with algal-based filtration methods, I decided on a lower-tech relatively minimal tank. I wanted something with only the absolute necessary equipment and those pieces of equipment needed to be very sturdy and low maintenance. Tired of constant topoff, I also wanted a smaller tank with lower surface area that would require less.

 

Having had reefs for many years and keeping "sps" type corals for a good portion of those years, I also wanted to try something different--something you don't necessarily see every day. Thus, from this and the above, the idea to start a planted-type tank with a few corals came to be. With strong enough light, I could encourage enough primary productive growth to soak up all the nutrients I could add to the system as well as produce what I would hope to be an attractive display. The anemone idea came a bit later after I decided on a replacement for my old H. crispa--and out of feeling somewhat sorry for my clowns after losing her.

 

Anyway, enough rambling on my part and down to pics from the start of this project:

 

Day 1: Animals still alive in old tank started looking bad, so I was rushed to set up the tank immediately, despite the fact that I had intended to let it stabilize for several weeks prior to adding livestock. No lighting available yet, except for the 2-40w fluorescent lamps and the sump has not been constructed yet. Not a good start and things started looking bleak from the beginning.

 

Seagrass looking sad and yellow in the 3000K lamps:

 

FTS:

 

 

Week 2, now upgraded with Aquamedic 250w DE fixture. Things looking a bit better--maybe a turn of good luck?:

 

FTS:

 

Completed sump (finally--about 3 days after getting the new fixture):

 

Week 3: No light at all. My 40w lamps were now stuck in the sump and the Aquamedic fixture stopped working properly (and bulbs couldn't be removed). Things start looking really rough again:

 

Weeks 4-5: New and current fixture finally in. The glass grew a thick beard of filamentous algae that managed to keep the rest of the tank pristine:

 

Clowns in a thin area I scraped:

 

Seagrass already spreading quickly:

 

 

And... with clean glass and slightly clouded water from the maintenance (7/28/2010):

 

 

Tear-down to rid tank of Aiptasia (4/22/2011):

 

 

Tank as of 4/22/2011:

 

5/6/2011:

 

Tanks as of 11/6/2011:

 

Tank as of 3/9/2012:

 

Plus a short video on 3/9/2012:

 

Tank as of 4/30/2012:

[Guest TheBlueLorax]

i did what kind of seagrass

[Amphiprion1]

i did what kind of seagrass

 

Thanks! It's Halophila decipiens. I need to add a livestock list to the top

[Guest TheBlueLorax]

Paddle grass nice so are you dosing any nitrates?

[Amphiprion1]

Paddle grass nice so are you dosing any nitrates?

 

No. I'm currently relying on heavy feeding alone to account for any N or P. I'm still having a bit of trouble keeping up with demand, so I've recently increased feeding. I'm really enjoying the explosion of 'pods, worms, etc. that are resulting from it.

[animalmaster6]

Very Cool Tank!!

[Guest TheBlueLorax]

No. I'm currently relying on heavy feeding alone to account for any N or P. I'm still having a bit of trouble keeping up with demand, so I've recently increased feeding. I'm really enjoying the explosion of 'pods, worms, etc. that are resulting from it.

 

Smart

 

How do stop all the algae from killing the seagrass pruning im guessin...

[Amphiprion1]

The filamentous algae only grows on the glass, since that is where the flow and light is strongest. The Gracilaria isn't really invasive, but it does grow quickly. It is easily controlled with pruning.

[Guest TheBlueLorax]

[Amphiprion1]

Very Cool Tank!!

 

Thanks!

[Uhuru]

Wow that Halophila is growing fast! I hope I have as much success as you.

[Amphiprion1]

Wow that Halophila is growing fast! I hope I have as much success as you.

 

It has surpassed my expectations, to be honest. This tank was started at the end of may (22nd or 23rd, I believe, so that's only two months of growth). Knowing you and your tanks, I don't think there's any doubt. You feed more than enough to supply the necessary nutrients and you have plenty of light. I think you'll like the nutrient uptake you'll get--it should reduce the need for water changes a bit, at least.

[yoshii]

Wow! Very nice tank!

[Amphiprion1]

Well, in my continuing efforts to experiment, as well as push limits with this tank, I've ramped up the amount I feed yet again. I'm now up to 3-4 cubes of food per day, along with pellets. I really want to see how far it can go before I get measurable concentrations of nitrate, as well as how the plant life will react.

[animalmaster6]

Definetly let us know what happens

[Uhuru]

What is your light cycle? I read that it doesn't really matter anything from 10 - 14 hrs. works fine.

[Amphiprion1]

What is your light cycle? I read that it doesn't really matter anything from 10 - 14 hrs. works fine.

 

The halide is on from 9:00 am to 5:30 pm, so 8.5 hours. Lengthier times may increase growth, but that would also increase demand. I don't really want any extra demand until I can see what the current limits are. I also don't think you'd likely notice that much of a difference, while saving a bit of energy and reducing the amount of heat emitted. JMHO.

[Amphiprion1]

Here's a testament to how tolerant this stuff really is:

 

 

This relates back to the discussion about substrate depth. As long as there is one portion of the plants that has decent substrate depth, the rest of the tank doesn't seem to matter. This is also in a heavily, heavily shaded area and the grass doesn't seem to mind that much, either. Slightly to the right of where this pic was taken, the grass is actually creeping up the glass. It has already managed to snake its way completely around this little tank. You can also see the apical growth in this pic--it's the little light green dot.

[Amphiprion1]

Quick pic update. You'll note that the water is a bit yellow, which is from my being lax on adding carbon. The tannin load in this tank is pretty heavy, so it is prone to yellow very quickly:

 

 

[Uhuru]

holy crap that is really lush! awesome!

[Amphiprion1]

holy crap that is really lush! awesome!

 

Thanks. It is growing quickly again ever since I started plucking leaves. I'm having to literally dig my anemone and few corals out to keep them from becoming grown over. The other crazy thing is that the grasses finally outcompeted my Gracilaria. As they forged onward, the Gracilaria kept shriveling. Same with my Penicillus. It's pretty much going to be exclusively grasses now, since I can't get anything else to do well anymore.

[Amphiprion1]

No newer pics yet, but I have made some changes. I introduced a single new coral--a nice little colony of Pocillopora--a few weeks ago. It started out brown with pinkish growth tips, but has since turned completely pink under the halide. It has done well in the flow of the Vortech. Also, I've had to move some corals around and try to get them away from the grass. I'm finding out very, very fast that seagrass will indeed smother corals if they aren't trimmed in the vicinity. When conditions are good, I can confidently say that they will be the absolute dominant organism in a tank, outcompeting just about everything else, not only for nutrients, but space as well. The bare spots that were present have since completely filled in. I got another small, localized patch of dead grass, but it seems that it follows the course of the oldest rhizomes--in other words, I think the ones that "randomly" die have reached the end of their life span. Some recent finds I've made suggest that faster growing species like Halophila may only have a life of a few months at best. Interesting stuff and it seems to be supported from what I've been seeing.

[Amphiprion1]

Some updated shots. I've since added an extra powerhead to deal with the tremendous amount of buffering the grasses create. As a result, it causes the flow to really get low, which then encourages algal/cyanobacterial growth on the blades. It's maturing nicely, IMHO, minus the Aiptasia issue, which sort of goes hand-in-hand with this tank, considering the minimal filtration and high planktonic organism concentrations. They'll be my next project:

 

 

[yoshii]

Beautiful! Looking at your tank I think was what really made me finalize my decision about starting my own macro tank

 

I really love that oar grass, I tried to get some myself, but it didn't survive shipping

[animalmaster6]

Looking good!

 

Looks like the grass is growing excellent.