View Full Version : The Pentagon - 1800 liters - 475 gallon

03/10/2017, 09:53 AM

I'm introducing a build thread of my system. The main display is a rimless 'optic white' pentagon. In Europe, it is more common to use glass in stead of acrylic. Acrylic is more expensive over here.

The sizes of the main tank are 1,75m deep to 1,23m wide; two sidewindows, one of 25cm and one of 75cm and a front window of 138cm. Height: 82cm (75cm waterlevel).

On top, the display is strengthened with a metal frame which makes it possible at this height to work without glass pullstrips (if that is even an English word??)
whom are not disturbing my light reflections.
Beneath the display, There is the sump and a RO reservoir tank.

I've plumbed the connections of the return pump so that it's not only providing in water back into the display, but also providing water flow to the rhowapos filter and the zeovit filter (yes, I'm working with the ZeoVit system: sparkling colours for the SPS ;) ). The return pump also provides water to three other displays in the aqua room who serve as frag tanks and one quarantine tank.
It is possible to disconnect those of the system when needed.

The main display is the only thing visible from the living room.

Technique :

BBK 300 Deluxe
Red dragon 3 speedy 18m3 (150W)
2 Gyre XF280's + een tunze 6095
lighting: 3 ATI Sunpowers + 1 ATI Sirius X2 in the middle
+ Zeovitfilter, rhowaposfilter, GHL profilux 3.1N, vertex puratec 100 deluxe, DIY calcium reactor and a Teko 2000 chiller.

There is still a lot to do, for now only the aquaroom is tiled out, the tanks are in place and the lighting system is hooked up (possible to autolift the lightning system)

I'm planning my first occupants around July 2017, so that the water parameters and first animals out of the real life rock can stabilise.

Here is a first impression:





I'm the guy in the white shirt


I'm sorry if I've made mistakes to the English vocabulary. My mother tongue is Dutch ;)


Malign Reefer
03/10/2017, 11:03 AM
Looks an awesome build, I'm following along.

this is me
03/10/2017, 11:10 AM
Wow. Very nice. Can't wait to see how you aquascape the tank!
You will love the BBK deluxe 300 as I am.

03/22/2017, 10:45 AM
Unfortunately dropbox changed it's photo sharing links.. No longer very convenient to use. Since I don't have any edit rights on my build thread, I have no other possibility but to post them again with the changed URL. Sorry for that..





I'm the guy in the white shirt:


03/22/2017, 10:48 AM
Very cool. Did the available space make you choose the shape or was there a different reason?

03/22/2017, 10:54 AM
I chose the shape because the angle off view from my living room is better with a pentagon

04/03/2017, 09:16 AM
A little update:

plumbing: check, at least between the main display and the sump. The connection with my fraqtanks will follow in the coming days.
The most important thing, no leaks: Whoehoe..

images say more then words:

in order of appearance: quit failsafe, feeding pump, plumbing, zeovit and
BBK300 rinsing.
Wishing a week I'll pull the water out and fill it back with RO water and salt...


05/05/2017, 06:51 AM
the brown algaes

For the moment I'm in the brow algaes phase, All runs smooth.

The scape is temporary. I've just put the rocks in a general shape, but nothing is glued yet. Just te give me a general impression and possibility to change things. The scape will become a lot more open when I build bridges and such.

The big lines are left a reef with a cave in the front (will become a bit less high) with a slope that will run up towards the end to about ⅔ in hight. In the middle a canyon and on the right a bit more to the back a flat plateau about ⅓ in hight.
This will create a nice depth and as a photographer I keep some visual lines in thoughts. In the front I'll put more plate corals and to the back more acroporas which will enhance te slope effect even more.

You can't really tell from the pictures, but the rocks are minimum 15 cm from the edge so no corals will grow up on the windows and cleaning will remain easy.

I also keep in mind the size of full grown corals..

pictures say more then words:

General view from the living room (the upper panel will also be painted in anthracite color)




06/01/2017, 01:12 AM
The water parameters are good, so time for a few inhabitants. For the moment they are getting in shape in my quarantine tank:

seriatopora caliendrum:

ricordea florida:

seriatopora hystrix:

acanthastrea lordhowensis:


06/01/2017, 01:25 AM
Behind the scenes

What do you do when you have a day of and you have the home for yourself as the wife is gone working? Right: Doing some tank improvements..
It was time for my profilux installation and calibration. A fun job to do. Don't mind the cable work, that is for another time.


The settings when everything was installed initially:


Conductivity is calculated with the measurements of the temperature probe. These are in real density and not in S.G. as with a floating salt meter.
The 1.0229 density is approximately 1.0259 in S.G. ; with a temperature of 23,2C (74F) is 34 to 35 promille. This is double checked every week with my floating salt meter in S.G.

In the mean time, the redox is already to 295mV. A great indicator to sea that my tank is doing well. You can also visually see it in my main display as the green algeas are turning pale. So, that's a good confirmation.

other parameters:
NO2: 0 mg/l
NO3: 0 mg/l
PO4: 0,00 mg/l
KH: 8,6
Ca: 460 mg/l
Mg: 1380 mg/l

Forgot this one in the previous post, a monti plate:



06/01/2017, 04:07 AM
Wow very nice :D Thank you!

06/01/2017, 04:10 AM
Danke Michalinho. Ich brauche Deutche Zeovit. ��

06/01/2017, 08:52 AM
Nice job with the scape, looking good.

06/01/2017, 10:28 AM
Nice job with the scape, looking good.

Thanks but the scape is only temporary to have an idea and having easy access to pick the algeas. It's the global idea but will become a lot more open with caves, passes and hiding places. I've started fixing the left front cave with corallenzucht cement and is already a lot more attractive. I'll need another 20 hours or so to get it right. But it is coming 😁

Thanks for your nice words.


06/01/2017, 12:40 PM
hey nice and good luck!
you use a RD3 speedy 8m3 and a 18m3???
In the picture above I can see the big controller ...?!

06/01/2017, 02:36 PM
hey nice and good luck!
you use a RD3 speedy 8m3 and a 18m3???
In the picture above I can see the big controller ...?!

I'm using a 18m3. The smaller one is from my BBK300 which is also controllable
Cheers, Yoeri

06/02/2017, 05:31 AM
Very nice are u happy with the flow and power?

06/02/2017, 06:13 AM
Very nice are u happy with the flow and power?

Yes I am. I'm using it not only to feed the main tank. I also have bypasses to my other filters like the zeovit and deltic 509 for my rowaphos; aswel I'm using it to feed my quarantine tank and frag tanks.

For the actual flow in the main tank I use 2 gyre XF280's and a tunze 6095. In the frag tanks I use smaller tunzes. When the corals grow, I'll check wether it is enough or if I need some extra streaming pumps. But the gyres are pretty awesome. The first week they make some fairly anoying noise, but after that they are quit silent and produce a very nice flow not to compare with normal streaming pumps like the tunzes, vortex and others. The tunze I use is to randomly disturb they already random flow of the gyres whom are set in alternating mode and go from 10% to 100% every 2 sec.

07/23/2017, 07:56 AM
A little update on the tank. The scape is done:



Fish: 3 zebrasoma flavescens and 1 japonicus




07/23/2017, 08:13 AM
new corals:

07/25/2017, 12:54 PM
crap, none of the pictures are showing. They are killing all sorts of online communities!

07/25/2017, 02:51 PM
All of the images work fine for me. Perhaps it is your privacy settings.


07/28/2017, 06:45 AM
Since yesterday I have 3 new corals. The 2 acroporas have a little symbiotic crab :thumbsup:
When I put them in quarantine yesterday evening, I thought it was a AEFW. Luckily this morning, I found out that it was a symbiotic crab. Quite the difference...

blue acropora Sp.


acropora tricolor


Euphyllia divisa (frogspawn)


07/28/2017, 06:54 AM
Looks great! The tank looks really good built into the wall. Nice job!

Getting acros and finding those little crabs is awesome. I love those guys.

07/28/2017, 08:00 AM
Thanks Garret

07/28/2017, 08:35 AM
Looks awesome, How is that GYRE with a corner tank like that?


09/04/2017, 01:21 AM
Deze twee zwemmen ondertussen ook al anderhalve week vrolijk rond:

Acanthurus Achilles & Halichoeres chrysus


Het is wel niet de beste foto (rap genomen met de iPhone)...

09/04/2017, 01:23 AM
Deze twee zwemmen ondertussen ook al anderhalve week vrolijk rond:

Acanthurus Achilles & Halichoeres chrysus


Het is wel niet de beste foto (rap genomen met de iPhone)...

Sorry Guys, I was a bit to fast, I posted this to a Dutch forum as well and forgot to translate:

These two are swimming happily in my tank since the last week and a half. It is not the best picture as it was taken quickly with my iPhone...

09/04/2017, 01:56 AM
and it is a Halichoeres Leucoxanthus instead of a Chrysus (see white belly...):debi:

09/05/2017, 04:21 AM
... I cant see a pic

09/05/2017, 04:23 AM
... I cant see a pic
It is visible. Maybe some settings on your computer?

09/05/2017, 04:28 AM
It is visible. Maybe some settings on your computer?

yes I think the Firewall

10/02/2017, 01:56 AM
De ramen zijn wel niet gepoetst... De Achilles and Meliagrides still chilling:




10/09/2017, 08:26 AM
Looks awesome, How is that GYRE with a corner tank like that?


Hi Will,

Sorry, I overlooked your question... A bit of a late response, but here it goes:

I'm having mixed feelings with the GYRE. The flow as such is great, but whatever I do, opposing sides or 90 angle, the flows do bounce at the front window causing a swirl down. You cannot see this swirl, but it hits the sand and blowing it away from the bottom in the front. I've placed some plating corals over there and hoping that once they grow they will block the curl and leaving the sand in place.

I do have to say that I'm using very fine white living sand. Maybe with a bit of heavier sand it would stay in place.

That been said, on the other places in the tank however, it gives some nice sand lines or waves or however you would like to call it.

Cheers, Yoeri