New sand...new problem with flow.

[Gargamel35]

I have a 112 gallon tank with 4 powerheads. 2x Tunze 6095 and 2x Tunze 6055.
LPS and SPS tank.

I use them like this:
6095s are facing each other from the side of a tank, turned upwards and towards front of a tank. They are running at around 60% power in pulse mode.

6055s are on the back side left and right from the overflow. They are running at around 30% power and are pointed straight towards front.

This was an ok setup, current looked random enough.

I had 2-3mm sand and it didn't move. Now i changed my sand to 0,5mm to 1mm live sand. My powerhead setup creates craters in the front...It starts by blowing the sand away from corals that are at the front and then continious on from there.

So i try to help with repositioning but i get no success. It really doesn't matter how i position powerheads, problem stays the same.

Any tips how to position powerheads? It helps if i lower the power, (sure) but that is not the point.

 

[mndfreeze]

Maybe move them a little higher in the tank? Or if they can be angled at all, aim them a little upward. Once your sand gets a little older and has bacterial glue all over it, slime from snails, and all the goodies that make up a good sandbed, it will stick together better and not blow as easy.

There really isn't much solution other then lowering your flow or finding a way to aim it differently since you dropped to much smaller sand particles which are that much lighter and easier to be carried away. IMO I would try raising your powerheads up a bit in the tank. You can still have higher flow across the top half and less on the bottom and have a successful reef and once your sand has matured put them back to how you had it before.

 

[Gargamel35]

If i raise the powerheads more, they get an air vortex from the top sometimes and that is not good for the pump. I was thinking about running the tank with only 2 x 6095 pumps, but i don't get enough flow in the corners like that.

 

[homer1475]

I think with what I see in the tank, which is virtually nothing other then LR and a couple small corals. You would be absolutely fine with just 2 PH for now. When you get more in the tank, I would reassess the situation.

From the pics it looks as though you have 3 PH on the back wall, and only one on the side wall. It is the ones on the back wall that are blowing your sand around. I would move one of them so it was directly across from the other one on the side glass, and allow them to crash into each other. This will create chaotic flow where the 2 waves crash into each other. I would then remove the 2 on the back wall.

With the PH on the back wall you push the wave to the front glass which travels down the glass and over the sandbed which gets blown out in that area.

Honestly though, after a month or so there will be enough "snot" in the sand it won't blow around anymore. Least not like it does now.

 

[RobZilla04]

Have you tried the powerheads low and pointed upward? Long shot but I thought I'd toss it out there.

 

[mcgyvr]

I'd change the sand....seriously..
Sugar fine sand SUCKS for a reef tank for this exact reason..
Having made that mistake once I will never do it again.. Carib sea special floor reef grade is great and as fine as I'd ever go again..

Or at the very least add larger sand on top of the existing sand..

 

[reefteaser]

FWIW, I just changed from the special grade to Eden MiniFlakes in my 115 mixed reef. I run 2 xf250 gyres, and was concerned about it blowing around. It has not been a problem, although I do run the gyres at a reduced rate, no higher than 30.
The MiniFlakes are really nice, hope I can still say that a few months from now.