View Full Version : Calcium reactor owners--question for you

Larry M
05/25/2000, 04:46 PM
Two people in the past week have asked me about the benefits of controlling the output from a reactor with a valve before the water enters the reactor instead of after. The idea here is to get away from that output flow valve clogging over time.
I have never tried this but in thinking about it one concern would be starving the circulation pump and possible burning it out. Is anyone doing this and how is it working for you?

Larry M

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05/25/2000, 05:39 PM
Interesting, but is the output flow valve so prone to clogging? I have had a reactor since September and I'm using a simple 50cent green plastic valve. Seems to be doing the job just great and if it ever does clog, hey its only 50cents! I think your concern regarding starving the circulation pump is a valid, it doesn't seem worth it IMHO.

05/25/2000, 05:42 PM
Just bringing this to the top, this is something that i've wondered myself Larry.


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Vins Fins
05/25/2000, 06:19 PM
Hi Larry,

I've run it both ways, if you inst the valve before the reactor, don't worry about burning up the pump.if the valve gets plugged up then no water can enter, and therfore no water will leave.the water will just recirc.
I pesoally like the valve after evrything,only because it is easier to adj the out put flow, the out put flow is very important, i use a stop watch to calibrate it. if you're worried about it getting plugged, then up you're c02 psig to around 30#'s. I have no trouble with it clogging.


05/25/2000, 06:20 PM
I have a lumar reactor which has the flow control on the input side and never had a problem.

05/25/2000, 06:38 PM
I want to add something to what Vinny said. It's true that if no water come in then no water will come out unless your CO2 gas keeps on coming in. Eventually it will force all the the water out and the recirc pump would have the potential to run dry. JMO

05/25/2000, 06:44 PM
I am having problem with the accurate flow through the Ca reactor when I first set it up. The main reason is I just fed it with gravity instead of hook it to the return pump. I did not wanted to spend the time to redo the plumping so I got a dosing pump for it instead. Very easy to control the rate with dosing pump and not worry about the flow rate increase or decrease. Already spended 700+ for the reactor, what 100 dollars more?

Minh Nguyen
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Vins Fins
05/25/2000, 06:57 PM

as long as you're output is at the top of the reactor then the c02 will either push out the plugged area, or if the c02 regulator is set to low it will act like you're soenoid valve and stop flowing c02 as well, that is why i like to run the c02 pressure a bit higher.no more than 35#'s max, don't want anything cracking or the air line tubing breaking. I 've found that the c02 will work its way to the top and purge itself out of the
output line, even if it gets a little plugged.
I once had it go for three days with no water dripping from the out put and the water level in the reactor remained the same. the reacotr pump was just recirculating the water, no problem at all.


brandon higbee
05/25/2000, 06:57 PM
i have red sea lg model it works that way and it works fine the pump is internel the feed is by siphon works great two years running not a problem yet good luck brandon

05/25/2000, 07:22 PM
I also have tried it both ways and like the valve at the output. If you go with the valve at the input I think it needs to be at the reactor and not the pump. I also recently had to tee off the main pump to feed mine, I had it drawing water out of the sump and for whatever reason it quit doing it.

george w.

my diy skimmer/reactor (http://hometown.aol.com/geos75reef/index.html)

05/25/2000, 10:14 PM
Geez Larry, I ask you a simple question and you have a thousand people check it out. Bottom line, a valve on the input works a little better than a valve at the top of the output, but really it's six of one and a half dozen of the other. Agu

Larry M
05/25/2000, 10:24 PM
Agu--I thought you didn't have it running yet? How do you know it works better?

Larry M

Visit Reef Stores.com ( The liaison between hobbyists and on-line retailers.

See my tanks at Northern Reef (http://www.reefcentral.com/northernreef/index.htm)

Clam Man
05/25/2000, 11:08 PM
Here is the solution to anyone having trouble with the clogging at the output. Some reactors take the effluent from the botom of the reactor and this allows the micro particles getting to the valve. Also if your water recirculation is too fast and your reactor has the output at the top of the reactor the particles will be in suspention anyway and make thier way to the valve. SOLUTION: About 6 inches before the output valve install a sediment chamber in the line. Larry your handy with acrilic, you can built a 4"x1"x1' chamber or you can make it out of pvc and cap the ends. As the water moves through this chamber the water flow will slow enough for the sediment to drop out of the effluent. Do not worry about the Ca++ precipitating out of solution because the water is not stagnate and does not have enough time to precipitate for fast reactors (effluent flow of >1 liter/hr). If you have a slower reactor (smaller bioload) shorten the length of this chamber not the diameter. Any questions let me know.

David Newman
05/26/2000, 05:51 AM

For the first 3 weeks or so after setting up my (your) reactor the valve on the outflow would gradually clog over the course of 2-3 days slowing the flow to a crawl. After approx 3 weeks the problem disappeared. For lack of a better explanation, I attribute the early problem to a failure to adequately rinse the media.


05/26/2000, 07:02 AM
I have a Precion Marine calcium reactor and the flow valve is situated on the incoming side. I'm having a hell of a time getting the outflow rate stable. Any thoughts?

05/26/2000, 07:36 AM
Does the pressure inside the reactor affect how well it works? I made my own reactor, and I put the valve on the output and the feed is from the skimmer pump (so there is a good amount of pressure on the input). I did this so I could have a higer pressure inside the reactor and thus dissolve more CO2. This might not be making much difference at all though. I haven't tried it the other way. Anyone have any experience or theories on this?

I haven't had any problem with the output cloging (4 months now). Are the valves cloging from dust off of rubbing media granules, or is it clogging from precipitation of CaCO3? It seems that the CaCO3 would be unlikely to precipitate inside the reactor, where it is supposed to be dissolving. On my reactor, the tube where it drips into the sump is encrusted at the end where it comes out, but the hose is clear and I can't see any white stuff anywhere near the output valve. If the output is getting clogged with dust, then maybe the recirculation is too vigorus, and the media is grinding itself into dust.

My $0.02

05/26/2000, 06:18 PM
We have a Knop C and the restrictor is on the output and it works fine. It may depend on the type of output valve you use. :)

05/26/2000, 06:34 PM
Clam Man, do you have a pic?


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05/26/2000, 10:20 PM
Larry, clam man told me about the potemtial problem at the last club meeting, and his solution also. with the design of my/your reactor it shouldn't be a problem. Yeah, I set it up today and everything seems to be OK, but the needle valve is really touchy. Interesting side note, the connection from the co2 tank was leaking and my dog got really wierd. He kept walking around the room sniffing everything with his ears back, and finally focused on the sump. After I found the co2 leak and fixed it he mellowed out.

05/26/2000, 10:23 PM
Hey ya Larry :)

As with most things, 6 of one, half a dozen of the other. Each has it pros and cons. Personally I have the control valve on my calcium reactor on the output side of the reactor. Here are a few ideas that come to mind for either way:

Input side

Flowrate influenced by pump pressure and valve, including degree of blockage.

Reactor operates at just slightly above atmospheric pressure.

Less likely to clob up, due to the lower calcium carbonate content of the water, and suspended solids.

Output side

Flowrate influenced by pump pressure, valve, and carbon dioxide pressure.

Reactor operates at above atmospheric pressure, effected by pump (largest otherwise doesn't work) and carbon dioxide pressure.

More likely to clog up due to the fact has high calcium carbonate content i.e. easy to precipitate, and suspend solids likely to be higher due to the substrate in the column dissolving into smaller grains.