(MyReef) Nilsen reactor update

[danmhippo]

A couple of months ago, there was a discussion on the nilsen reactor. I, like many others were having problems with it. I sent mine back to Andy to inspect and for him to figure out why it does not spin correctly.

The reactor was damaged during shipping, which Andy complimentary repaired it for me. I received the repaired unit back a couple of weeks ago and finally installed it (after I decided to get my plumbing organized.....).

Andy did not make any changes to the structure itself. He simply replaced the broken bottom stand and glued a new wearplate on top of it. He did, however, replaced a new hanna stirrer for me as when he was testing it out at his shop, the old unit responded sporactically and he determined the old unit is defective.

The repaired unit work flawlessly now. I initially tested it with only a cup of kalk powder and have the stirrer set to spin 24x7 at low speed. 2 weeks later, I increased the kalk powder to 3 cups and the unit is still working great. With 3 cups of kalk, I increased the stir speed up to 50%, 24x7 still. I expect the 3 cups to exhause in another 2 months and I will try to up the dosage to 5 or 6 cups and see if it will pass the torture test.

For those that are having problems with stir bar not spinning, I'd suggest you leave your mag-stirrer on 24x7, but choose a lower speed setting to allow kalk powder to settle out of the top portion liquid of the reaction chamber. This way would avoid the problem of kalk settling on the spin bar and hardened.

 

[SPC]

Hmmm, have you tried it without it being on 24/7 Dan? The original idea was to have it come on only during certain hours of the day for only a few minutes at a time.
Steve

 

[danmhippo]

No. I always have it on 24/7. Remember when I first got the nilsen (with the old hanna), kalk would settle around the stir bar and harden. Now thinking back, I don't know if it's the defective hanna that make it not work, or the brand of kalk make it not work right. But anyway, I set it 24/7 from then on. Besides, the power drain on the mag unit is way less then other electrical equipments we typically have anyway.

 

[SPC]

Now thinking back, I don't know if it's the defective hanna that make it not work, or the brand of kalk make it not work right.

-I don't know, why don't you try it with all the major brands of kalk like I have and see if it works as intended to. I sure would like to know if yours will work shutting it on and off on a timer.
Steve

 

[danmhippo]

Ugh........... I don't know, Steve. I hate messing around with something that's already working. Afraid after messing with it, it will no longer do it's job. I remembered last time I was fooling around with the temp controller where you can select cooling mode or heating mode. I must've played with it and forgot to set it back. The heater never turned back on and the tank temp plummeted to low 60's.

I will see what I can do here. I will shut it off for 12 hours and see if it will come back on tomorrow morning.

BTW, in return, can you stick your fingers into the anemone's mouth for 2 minutes and see if it will digest your fingers. I have always wonder about that but never had the guts to do it.


hehehe................. :twisted:

 

[bowfront]

SPC

I'm still using mine without any problems. It is set on a timer to come on 4 x day for 1/2 hr. each time. I'm not sure if this is the best on/off method but its been working fine so far. I have never experienced harding of the kalk at the bottom or had the stirrer not fire once the unit is setup properly. I add 1 1/2 cups of kalk about every 3 weeks. I've been using a commercial calcium hydrozide brand named Codex but have recently purchased some ESV and will try that next kalk change.

Several mods that I did recently seem to work pretty well. I glued a piece of acrylic to the 2 sides of the base to create a fixed bottom that I set the Hanna on. To this bottom piece I attached thin strips of acrylic on either side and back of the perfectly centered Hanna so that I can easily slide it in and out as needed without searching for the sweet spot. I also added nylon wing nuts to the 8 screws that fasten the top after stripping one hole on the flange. These are simple 1/4 20 thread and cost me about 2 cents each at U.S. Plastics. They allow you to really tighten the top down without worrying too much about stripping the flange.

 

[SPC]

To this bottom piece I attached thin strips of acrylic on either side and back of the perfectly centered Hanna so that I can easily slide it in and out as needed without searching for the sweet spot.

-Thanks Bowfront, I agree this is necessary in order to keep the unit running. I will probably give this a shot and see how it works.
Steve

 

[Nelliereefster]

Silly question...

I'm not familiar will nilsen rxtrs. How do you control effluent parameters, to ensure Ca, Alk, pH are where you want them to be in the reef?

In what ways are nilsen rxtrs better/worse than calcium rxtrs?

 

[golfish]

Running it 24/7 isn't the answer. Depending on evap there probably wont be enough time to settle out. I still say those Hannah units are not strong enough on the 6" models.

I have a large mag stirerr on my 6" MyReef reactor. Its works great but I would still lke to see Andy build these units using something like an Ehiem pump over a mag Stirrer. Of the two Kalk reactors I have used the pump mixed unit is more user friendly.

 

[JeremyR]

Yeah, it really seems like this stirrer thing is more trouble than it's worth.. there are a number of people using pump driven units that have dispelled the it kills your pump super fast thing.. you just need a half way decent pump. And even if the pump dies, you don't have to send the thing back to get it serviced.

 

[danmhippo]

Steve, the unit fires back on after 12 hours of settlement.

I would agree the pump version of the nilsen reactor is a more user friendly way to go.

 

[SPC]

So are you going to see how long it keeps doing this Dan, or go back to 24/7? BTW, mine starts back up after 12 hours also, sometimes :wink: .
I have solved the problem with mine though, what I do is pick up the reactor and give it a shake a couple times a day, works every time :wink: .
Steve

 

[golfish]

Yeah, it really seems like this stirrer thing is more trouble than it's worth.. there are a number of people using pump driven units that have dispelled the it kills your pump super fast thing.. you just need a half way decent pump. And even if the pump dies, you don't have to send the thing back to get it serviced.

I used a Geo kalk reactor for 8 months. It was mixed by a MJ1200 mounted externally. During that time I lost one blade on the impeller and the thing never ever leaked a drop of water. I think if Andy built the reactors in the same shape as he does now he could mount the Ehiem pump where the mag stirrer unit is and run the pipe up through the bottom (not sure on this one) The cost to build one of these units would be cut not to mention the easier operation.

I have solved the problem with mine though, what I do is pick up the reactor and give it a shake a couple times a day, works every time :wink: .
Steve

Steve,
Next time try taking it out on the balcony and hanging it over the railing

 

[danmhippo]

So are you going to see how long it keeps doing this Dan, or go back to 24/7? BTW, mine starts back up after 12 hours also, sometimes :wink: .
I have solved the problem with mine though, what I do is pick up the reactor and give it a shake a couple times a day, works every time :wink: .
Steve

Hey, here is a idea. You still got one of those vibrating beds?

 

[SPC]

You still got one of those vibrating beds?

-Dan, that was supposed to be a secret .
Steve

 

[Osama]

I will add my experience. Since Andy sent me the longer stir bar (3+inch) and I am using the larger motor he supplied with the 8inch diameter tube and I placed the thin wear surface on the inside bottom of the Nielsen. I have had no more problems with my unit. I ran it every 4 hrs for 5 minutes. It worked fine with 1, then with 2cups of Kalk. I am now running my unit 10 minutes every hour. I add Kalk every month or so. Ttrying to see if I can get by every other month by increasing the amount of kalk. I noticed that the effluent Alk is not as high just before the unit stirrer comes back on so I increased the stirring frequency. I would appreciate it if others tested their effluent just after & just before the stirrer goes on and let us know their alk readings. I also gradually reduce the speed of the stir bar as the amount of kalk is used up.... I am not sure that I would like to go to a different system BUT I am not familiar with the outside pump....

 

[SPC]

and I am using the larger motor he supplied with the 8inch diameter tube

-And that IMO is why it works well :wink: .

Here are my numbers on the effluent alk osama:

Full strength limewater (3 tbs/ 1 cup of water) = 12.41 (this is supposed to be total saturation).
Alk out of reactor = 12.23

Remeber, I am not stirring at all, I give the reactor a shake in the morning and again at night :roll: .
Steve