Hydor Koralia Water Circulation Pump

[Kurt_Nelson]

Originally Posted by Agnate80700

Dont get me wrong, I love my hydors I think they do exactly what I need em to. They just need to be placed so you get the most out of em.

I just replaced a MaxiJet 400 (100gph) with a Koralia 2 (600gph), and wanted to reiterate Agnate80700's point... the pumps are great, but don't expect to place them exactly where your old ph is that you're replacing. You'll need to rethink your placement for good current.

With the larger flow, I was able to move the Koralia onto the back wall (and hidden behind a rock) of the tank, and bounce the current off the side and then again off the front - kind of a double-bank shot. With the smaller MaxiJet I replaced, I had it on the side wall to start with. The end result was that I got a tad bit more current, but more dispersed... and was able to hide the ph behind a rock.

When looking at the gph ratings of the Koralia's, don't get fooled. I really had to trust the guy at my LFS that the 600gph Koralia wasn't as fierce as I was thinking, especially since I was looking at swapping it for a 100gph ph. Glad I listened to him because as Agnate mentioned, the flow is so much more dispersed, you can't really compare the gph figures of these new pumps with the more directed flow of the MaxiJets. A more useful figure that ph manufacturers should give us is the water velocity at a point a couple inches in front of the output. That's really the number we're all interested in.

[pinda]

I agree with you Kurt. I was a bit concerned at first that they didn't seem very powerful, but I can finally see detritus floating in the water column instead of sinking straight down. These also allow me to easily change the flow patterns in my tank. The only problem I have is that one of them the spindle slips ocassionally and this causes the flow to stop. This only happens when there is a loss of current.

[chase33]

I've had my 4's for months now and have been very happy with them. The only problems is as someone mentioned above. I have trouble positioning them so they don't create a large crater in my sand. Have not been able to do so but the sand isn't that bad.

[gheitman]

I was considering one of these for my 29 gallon tank but was afraid that the flow rate was too high (especially since I am using sand). I ended up getting a Maxi-Jet PH 600 instead. Otherwise I've heard nothing but good things about the Koralias.

[dianeww]

I have a 75 gallon, and I recently replaced my old maxi-jets with 4 hydor koralia 1's. I have two in the back left upper corner and two in the back right upper corner, one aimed up and one aimed down forward in each corner.

The flow is strong yet dispersed, and my sand has never been kept cleaner. When I think of it, I pull two of them out front overnight ( they move so easily with the magnets) and shoot them directly across the front of the tank. So my front sand is also really cleaned and slightly stirred. I haven't had the problems some here have had with craters. I keep them high in the tank, maybe that's the difference.