I have been stuck at work drawing stuff waiting until I could get home to take some pics of recent progress to give you guys an update. I just remembered that i had some crappy pics on my phone so, whilst the pics dont show everything, at least its a bit of an update.
The last wet test (back in Feb) went well, I left the system running for a couple of weeks with just RO and just observed it to see if it was running how I wanted it to. On the whole I was very happy but there were a couple of things i wanted to change. Back in February I didnt have sand in the tank and the plan was to just leave the tank full and add the sand via a drain pipe and hopper. Because there were some plumbing tweaks I wanted to make I decided that I would drain the tank down, make the changes and add the sand dry. That was back in February, work has kept me busy and sleepless until I could find the "me-time" to play with the tank.
The biggest bug bear was the returns from the sump. Each of the two return pumps terminates tank side via a calfo loop...two pumps, two calfo loops. Each of the loops alternated between an outlet that pointed across the DT surface water and one that pointed down towards the reef.
In this pic you can see the "t's" pointing downwards and the "t's" pointing across what will be the water level.
The outlets that pointed across the surface have flexible loc-line hoses and 3" flare nozzels
Due to the extra (albeit slight) resistance on the outlets pointing across the surface it meant that the outlets pointing down took most of the flow. This left me with less surface agitation than I would want.
So the first "tweak" to the plumbing was to remove the outlets that pointed down towards the reef on both the calfo loops. (pic to follow)
Secondly...does anyone remember this mess?
This was my plumbing nightmare to plumb 4 cls pipes, 2 returns and a water change pipe around a 4" drainpipe. A stupid error on my part meant that the core hole through the house hit a downpipe in the centre leaving me no room to work with.
Having been stuck at work for the last 3 months it gave me time to think/worry about the effect all of the bends would have on the frictional loss for the closed loops. I will be paying the running costs for the pumps to give me 100,000 lph of flow in the tank, it seemed pointless if the frictional loss would reduce that significantly.
I never had the chance during the last wet test to examine the CLS flow so for all I know it would have been adequate. The thing that concerned me was that once the tank is running it will be extremely difficult for me to amend the plumbing and the tank isnt built in a fashion that would make adding powerheads easy.
So while I had the tank drained I decided to alter the CLS plumbing aswell
The first step was to drill 4 additional 44mm cores through the walls.
This meant that I could take the 40mm pipe straight from the pump, through the roof of the fish room, through the wall and to the tank.
This is view from the fish room roof
This meant that I was able to re-do the returns plumbing and had more room to work with making less bends and a more direct route to the tank.
I will update with more pics when I get chance
With the tank drained it made adding the sand an easier task.
I ordered 1 tonne of fine sand to create the DSB and RDSB.
The DT took 550kgs to get a 6" DSB (on average) I used a tape marker on a piece of pipe to give me a guide