New Oceanic Tech tank build

[ZenMastr1968]

Well, 1400 GPH has turned out to be too much for my tank..... While at work yesterday, the sand at the front of the tank ended up in the middle of the tank, burying the first layer of LR (and any corals just in the sand) and all the suspended particles in the water sandblasted my Xenia - all but decimating it...

When I got home I tried to readjust the maxi-jets to go more above the rock and sort of at each other, but the damage had been done and it still looked like too much current for the three fish I have - they were huddled inside the rock or in the bottom corners. I shut the experiment down and put the two mini-jet 606's back in. I know they are not enough flow (because there were dead spots in the corners), but it was enough to make things happy.

The 606's are rated at 153 GPH and the unmodified maxi-jet 600 is rated at 160 GPH so they may not be the best replacement choice, but I do like the mounting of the maxi-jets better and there are the magnet mounts I want to get down the road, so I'll probably try putting the 600's back in (unmodified) and see how that goes. I was looking at the VorTech's and Tunze streams w/controler, but at $800 to $1K - it's not going to be anytime soon...

I think something aroun 700 GPH is the magic number and I really like the way the propeller pump mods were churning the water - just not as much as it was

Anyone have any thoughts on what I can use to get to that number? I was looking at the Koralia 2 pumps, but they say they are not for use in wave makers...

 

[dedfish]

I don't know if you saw my response in my thread but for now I'm using 1 modded 600 that supposedly puts out 1400gph. I'm not having any significant issues with the sand getting blown around. I have it placed so that it's about a foot deep and pointed at the center of the front glass with a slight upward angle.

 

[ZenMastr1968]

I don't know if you saw my response in my thread but for now I'm using 1 modded 600 that supposedly puts out 1400gph. I'm not having any significant issues with the sand getting blown around. I have it placed so that it's about a foot deep and pointed at the center of the front glass with a slight upward angle.

I did see, I have (had) 2 - one on each side about 3" below the waterline pointed downward at the center of the front glass. Each was on a timer that alternated between the two (whatever the shortest time possible is on that coralife wavemaker) - only one was on at a time. When each was on, I would see the sand at the front, center of the glass move a bit (one would make it do it more than the other - one side has more rock to go around than the other) and I tried to adjust them to minimize the shifting sand.

It was looking a bit rough in there Tuesday night (the night I put them in) so I left one off and just let the other be on it's normal cycle - which would have made the one pump be on for 5 or 10 min, then 5 or 10 min of nothing but the return. It run this way overnight. In the morning (Wed) things didn't look too bad, the 3 fish were hiding, but I figured they would eventually get used to the higher flow. So before leaving for work, I plugged the second pump back into it's side of the timer (so they were again alternating) and left. Late yesterday afternoon my wife told me that "my tank needs attention"....

When I got home, for pretty much the entire length of the front of the tank, there was about 1 and 1/2" depth of sand backwashed into the center of the tank, covering everything that was there. The water was all cloudy with particulate and there was sand sprinkled all over the LR. My Xenia was pretty close to the path of one of the pumps and took a beating (this morning when I looked at it there was only one stalk left and it was laying down).

Like I said, I tried to readjust the 600's so they were more pointed up and down the lenght of the tank (at each other) and pushing against the LR. They were too close to the surface and were causing whirlpools until I moved them down a bit. A few live rock pieces were moving in the current and although it wasn't shifting the sand anymore - the fish weren't happy and still hid.

I was really hoping to be able to keep these pumps out of sight (more or less) by keeping them toward the upper corners - for some reason they are not as noticeable there.

If I get a chance tonight, I'll remove the mods on the 600's and try them again with the spray nozzles I have on the 606's

 

[ZenMastr1968]

I've been working late the last few nights and haven't been able to work on the tank. With the lower flow pumps back in there (the 606's) the clarity has come back and the fish are happier, but I can see the flow is a bit too low.

The Xenia is in fact caput....though there may be hope. The stalks have all died off (and fallen off) but the foot of each stalk is still attached to the LR, so maybe with time it will regrow.

I'm hoping to attend tormorrow's meeting/auction and will be spending a good chunk of time over the weekend in general looking at a way to get these pumps put in the tank in such a way that everything is happy.

 

[ZenMastr1968]

I spent most of Friday thinking about the flow problem in the tank. Trying to approach it scientifically.

I looked up the specs again on the algae free kit - black prop (which I was using) and it is rated by the manufacturer @ 1400 gph on a maxi-jet 600. I looked up the sure-flow kits for the maxi-jet 600 and they were rated at 800~1000 gph. I took a close look at the enlarged pictures of the sure-flow kits and the prop assembly didn't look any different - in fact they say they use the magnet assembly from the maxi-jet maker in Italy....so I started thinking. Chances are they are both using the same magnet assembly and shafts (because they truly look exactly alike). The maxi-jet 600 pump is turning at a constant rate. So the only difference has to be in the shape and overall design of the propeller itself. I thought about purchasing replacement sure-flow 600 props and put them into the kit I already have - would help off-set the costs so far. But, I've modified impellers before to adjust flow rates with HOB filters and such, so why couldn't I modify a propeller to reduce the flow on these mod kits. I really like the circulation and pattern that the propeller based pump gives, it's just too much for my tank - in my opinion.

I have the 2100 props from the kit and I'm not imaging that I will be upgrading to maxi-jet 1200's anytime in the near future, so I took a look at the possibility of modifying those(and that way still have my original 1600 props). The 2100's are made with a white, softer, plastic/vinyl material. That's good since it would be easy to trim with a standard x-acto knife,but may not end up being that durable in the long run - I'll take my chances without spending anymore money right now...

I made a paper pattern of the 1600 prop blade and used that as a starting point for modifying the 2100 props. I marked that on the prop and then trimmed it down with the x-acto knife. I then trimmed it down a bit more - to make a smaller prop with hopefully less water pushing power. I filled the bathtub with water and gave it a try. My first attempt was unbalanced and so the pump wobbled and made a lot of noise. Plus it didn't seem like the flow was any less than the standard 1600 prop (I put one in the other pump and put it along side the modified one for comparison). I decided against putting it in the tank that way and gave up on the idea.

Later that night, I couldn't sleep so I took another look at the modified prop and evened the sides out more. Then I went ahead and tried it out in the tank to see how it went. It didn't do too bad and there was no more noticeable hum than there was with the straight 1600 prop. the flow was reduced, but the was still plenty of circulation. I took and modifed the other 2100 prop like the first one and gave that one a try. It was a little more powerful than the first (even though it was the same distance underwater as the other, it would make a whirlpool from time to time) - cutting them by hand didn't make two exact copies (not that I was expecting to be that good at it), but overall it was a good start. I let it run that way overnight - both pumps running on the alternating cycle.

In the morning, things were still looking pretty good, but there was a little sand shifting at the front of the tank and the fish were still hiding in the corners. I decided to give the inhabitants a bit of a break that day and unplugged one of the pumps - the one that appeared to be most responsible for the shifting and just let the tank run with one pump for the day (cycled on and off with no flow during the time the second pump was supposed to be on). Everyone seemed to like that - the fish would hide a bit when the one pump was on and then come out when it was off. That night I trimmed the props a bit more trying to further reduce the flow and get the two pumps more equal. I also readjusted the direction so that the pumps were pointed toward the opposite corners so they would have the longest distance before hitting the tank walls. I let it run that way overnight.

The combination of the two seemed to correct the sand problem as there was no shifting in the morning, but still a good flow and I could see the sand on the sides looked a bit cleaner. It's run that way for the last day or so and still looks good. I guess there could be a little less flow for the fishes sake, but they were out a bit more last night when I got home. The torch corals seem to like the flow - they were about halfway extended when I got home (which is more like they were with the lower flow 606's). There might be an additional tweaking necessary to make everyone more happy, but I didn't want to cut it down so much that it wasn't enough. As I put coral over the top of the LR "reef", that might help reduce and further diffuse the flow so I may be at the "sweet spot" now. If the fish look like they are adjusting, I'll probably just leave it for now. Will definitely purchase a varible speed pump w/controller setup in the future - just can't afford it now...

As I get time, I will post closeup pics of the tank and the mods to the props. I've got a good growth of hair algae beginning on the upper areas of the tank and I can see some sort of whiteish bugs in the fuge, so it looks like things are starting to take off! I'll have to get a full CUC going in there around the end of the month (should be about right for enough growth for them all to live on). I only had the pistol, two large hermit crabs, two emerald crabs, 3 adult snails and a few baby snails left in the old tank that were brought over and I picked up a pepermint shrimp last weekend to help out. I'll have to run some new tests to see how the water is doing. Well that's all for now....