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300 Gallon Build Thread

BrendanG

CCA Members
Hey Everyone,

I’m a life long dmv aquarist who finally joined your site. It’s been about 10 years since I’ve last kept African Cichlids, but I stumbled across a tank at a price I just couldn’t pass up.

I’ve been an avid reef keeper since I tore down my old African Tank - a 72 gallon all male hap/peacock which met its untimely demise when an associate overfed it, killing my dominant male. This ultimately led to the weekly discovery of dead sub-adult fish as they fought for dominance.

I’ve since learned my lesson.
Those weekly pill dispensers have been a life saver.

That and a “pinch”, doesn’t register to about 98% of the human population

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BrendanG

CCA Members
I was fortunate to stumble across a Marineland Deep Dimension 300g from a SA and Ray Enthusiast. I’ve done the research, am more than familiar with all the horror stories, and understand that aquarium enthusiast acknowledges the inherit risk of keeping water in a glass box.

A deep dive on RC, R2R, MFK, and various aarowana forums appears to suggest - that in 2017 Marineland briefly switched manufacturers - with this business decision characterized by utilizing Black instead of Clear aquarium silicone on the bottom panel. The result was a string of “blow outs” - due to sealant separation.

Fortunately for me, this specific aquarium was manufactured in late 2015 - and came with clear silicone on the bottom panel.

A sucker for the “precautionary principle” - I had the tank delivered to my buddies bath renovation shop and got the tank stripped and resealed.

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BrendanG

CCA Members
The tank came with a large Amiracle Wet Dry Sump - I think it’s a total of 63 gallons. I knew mechanical filtration would primairly take place in the drip tray with filter floss. But the key to crystal clearwater has always been an established biologically active system.

After the ever amusing “pore war” debates online, poret foam to be the best option. I wanted both aerobic and anaerobic bacteria to be used effectively.

It had been a while since I’ve last kept a freshwater system. Reef keepers notoriously fear “sponges” and their propensity to become “nitrate factories” - but when it comes to providing surface area - I just need a ton of holes where biofilm can accumulate. If it’s light. Porous and easy to clean - I was more than happy to order a few slabs of 30ppi aquarium foam.

Whatever manufacturer science bias aside - I figured it was the most convenient and biggest bang for my buck outside of “pot scrubbies”

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BrendanG

CCA Members
With the tank received I painted the background and sanded/refinished the tank stand in a flat matte black.

The tank is placed in the basement with a vinyl flooring. Unfortunately the concrete isn’t perfectly level - so I incorporated some shims to ensure all was even.

After a week long leak test, I sourced someone breaking down a 180g reef tank and filled the tank with about 200lbs of aragonite reef sand.

I anticipated quite a bit of die off and a large ammonia spike - but figured that just letting the tank cycle amongst a few water changes over a two month period should do the trick. Plenty of nutrients to feed nitrifying bacteria - even if that means more voluminous water changes.

My biggest pet peeve at the moment is the flow rate. With the Mag 24, I’m not quite getting the flow I’d like - so I def think I’ll be needing to incorporate dueling power heads. It’s not bad, but it’s not great.

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Freakgecko

Members
Thank you! The best part is when a tank finally comes together and you get to sit back and watch the tank mature.
You used sand that was previously in a reef tank? May wanna check your specific gravity, you don’t want marine salt in a freshwater tank
 

BrendanG

CCA Members
You used sand that was previously in a reef tank? May wanna check your specific gravity, you don’t want marine salt in a freshwater tank

I did, thank you for the heads up! I have no doubt dilution and the handful of large water changes have remedied the situation. There was a lot of die off.
 

DiscusnAfricans

Past President
Love seeing new tank builds, especially on big tanks, so many possibilities! Being well prepared makes things much easier, very well thought out setup. Going back to African cichlids?
 

BrendanG

CCA Members
Love seeing new tank builds, especially on big tanks, so many possibilities! Being well prepared makes things much easier, very well thought out setup. Going back to African cichlids?

Thank you, this is the first "big tank" I've owned. Been keeping nano reef tanks exclusively for the past 10yrs.
African's were the jump into the SW world - so its only fair that I come back.

Looking to go larger peacocks/haps.
 

BrendanG

CCA Members
The tank had been filled October 25, but suffered a small leak in the plumbing. What it required was a layer of plumbers tape and a tightened fastener.

As to be expected I experienced an extremely high nutrient spike the first week in November and elected to complete an water change to pull those nutrients and give the biological filter a chance to play catch up.

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BrendanG

CCA Members
A few water changes later and the biological filtration has begun to catch up and my nutrients are at a manageable level.

I’d love to get my nitrates down past 10ppm - but that’s likely the ReefGeek in me who strives for perfect water.
The aragonite substrate is buffering appropriately.

I know dip tests aren’t perfect - but they’ve always seemed to give solid ball park estimates.



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IndianaSam

CCA Members
I’m really enjoying the build!

What kind of drain system are you using? Herbie, BeAn Animal? I can’t tell from the pictures.
 

BrendanG

CCA Members
You could use some plants as a nitrate sponge.

I’d really like to give Giant Vals another try. I’ve noticed they tend to do best with some fertilizer when just starting out to establish a root system prior to shooting out runners. If anyone has some that’s gone crazy shoot me a dm - I’d be happy to take some off your hands.

In the meantime I’m Looking to dial in my lighting with some simple par38s for the dramatic spotlighting and shimmer effect. Little bit of fine tuning required on my end as far as mounting options - the tank sits directly under a HVAC (I’d like to suspend them over the tank) and goosenecks/fixed arm’s 12-18” out is something I need to play with a little more.

Quick little sneak peek - I’m not quite satisfied with the layout/rock work yet. I’d like a little more open layout for predator haps/larger peacocks

I threw my first fish in last week. About a 4” star sapphire male - he seems to really be enjoying himself.

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BrendanG

CCA Members
I’m really enjoying the build!

What kind of drain system are you using? Herbie, BeAn Animal? I can’t tell from the pictures.

just the regular “durso standpipe” style that comes with the MegaFlow overflow kit. Because I do not have a fail safe/backup drain - I’ll have to ensure the single standpipe does not get clogged to prevent display tank overflow.
 
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