Prizm Skimmers

[Petey]

So I know that alot of people don't have many good things to say about the HOB Prizim Skimmers but that's too late for me now. The Prizm can very highly recommended to me from my LFS, but i'm finding it tough to adjust it properly. Does anyone have one of these skimmers, if so are there any reccomendations that they can give me.

Thanks

[XXFirefighter]

good luck !
Can you take it back ?

[logman17]

I have one on my 10g...

The most important thing is to get a good "slime" coat on the inside. This means 1-2 weeks of breaking in. In my case, I left the adjustment gate fully open while I was home, keeping a close eye on the collection cup. You will pull a lot of liquid for awhile. After time, you can slowly adjust the gate until the gunk inside the collection cup becomes thicker. A little adjustment goes a long way. After each adjustment wait 2-3 hours before re-adjusting. You will find a correct balance eventually.

The key to the prism, IMO, is patience. They get a bad rap from a lot of folks, but will do a pretty good job when adjusted properly. Also, make sure all parts are seated properly. I had to disassemble mine once b/c one of the o-rings was pinched, letting too much air in.

Lastly, it was a wise investment (for me, at least) to buy the surface skimmer and media basket attachment ($25 online). The media basket allows you to run carbon and cuts down on the mirco-bubbles.

HTH,

--Logan

[malkore]

I agree, these skimmers MUST break in, while other skimmers work before the slime coat forms.

I wouldn't run it full blast, or you'll get to see why people hate the prizm's - they overflow the collection cup in under 15 mins if turned up too high.

You want the water level, where it changes from visible water to a mix of bubbles, just below the big O-ring where the collection cup attaches. About 1/8 to 1/4 below that o-ring is about perfect.

AS far as adjusting it...think of the adjustment knob like a clock face...never turn it more than 1 minute in either direction. the prism is sensitive...turning it up 5 minutes will look fine...but you'll overflow the collection cup.

Also, the prism has a tendancy to lose it's siphon....just pinch the airline until it regains the siphon. there's no need to ever put the airline on the closed 'siphone start' plug...just pinch it to stop the airflow so it can siphon.
good luck.

[THeCheat]

Excellent advice, as I am just now testing out my HOB Prizm. Anyone else also notice that these things are quite loud? All my other pumps and filters are silent in comparison. Can I put this Prizm on a sump underneath my tank and still get the same results??

[Petey]

I've had the skimmer running for about 2 weeks now with my tank cycling with the LR. I would expect get get much skim yet.

As for adjusting the water level to be just below the 0-ring, I'm running it probably 1/4 to 1/2 below the o-ring and if I increase the flow any I get a bunch of white bubbles coming into the collection cup that break down into water. Are these bubbles what the skimmer supposed to be taking off or should I keep the flow where I have it until the slime coat forms.

I must agree that the Prizim is quite loud, I this is is due to the function of the skimmer though. Anytime that there is cavation in water there is going to be noise, and cavatation is the basis of this skimmer! I had my air line loose for a while and found that the skimmer became quieter when I attached it to the port on the collection cup.

[logman17]

Sounds like the right level to me. You want dark, nasty foam, not white or clear. It will start producing when there is more waste/protien in the water. Mine was on for a cycling period with live rock and took about 2.5 weeks to produce skimmate.

Leave it where it is, IMO, and give it a week or two more. Mine pulls only about 1/8 cup per week out of my 10g, but there is not much bioload yet (die-off from live rock only).

Definately quieter with the air line on the collection cup.

--Logan

[malkore]

Petey, leave it adjusted where it is. You want a darkish, kind of brown/deep green stuff in the collection cup...almost like murky swamp water. It'll also have a very funky smell, so don't spill it on the carpet.

If the tank's brand new also, there won't be much to skim out.

and any venturi style skimmer is going to be noisy...the prism is nosier than a remora or cpr bak-pak though.

[Clown Monarch]

Alright, I'm here in defense of the Prizm. I just got Malkore's old one about a week ago and I must say I'm very happy with it so far.

It was easy to assemble, I got the siphon started quickly. Simply hold the primer hose until the siphon is running strong and there are no bubbles in the tube. I haven't lost the siphon yet. Once it's going, adjust the flow rate to the point where the foam is just entering the bottom of the collection cup.

I set it once initially and haven't touched it since. It hasn't overflowed and has been producing lots of skimmate in the past 4-5 days. I was prepared with the patience of Job to get this skimmer working properly, but so far it's been a breeze.

I may end up eating my words in a few weeks, but for now I'm happy.