Ca Rx: Geo 418 or 618

[jrgilles]

Hey guys, after doing a lot of research, I think I want to get a Geo calcium reactor. I've read a lot of good reviews online and everyone seems very happy with them.

I'm having trouble deciding which one I want to go for though, the 418 or 618

418:
Pros:
Up to 125 gallons (my DT is 75 gallons, system is 120) so it seems like the right size
Less expensive than the bigger model

Cons:
No pH probe holder
Uses a maxijet pump instead of an eheim pump

618:
Pros:
Eheim pump
pH probe holder

Cons:
Up to 350 gallons, so a bit too much for my system (unles I later decide to expand)
Costs more



Is it bad to get one that is rated much higher than my system? I think it isn't, since I can just drip less?

If anyone has experience or advice on these models, please let me know.

I'm currently leaning towards trying to find a used Geo 618, mostly for the pump and probe holder. If you guys have experience with the 418 and the pump does a decent job, that might be a better option (and I could even afford a new one of these if I can't find one used.)

Is there some sort of magnetic pH probe holder I could add into the 418? Or would I need to drill a hole in it to take a pH probe?

Thanks for any input you guys can give me on these models

rob

 

[danno14]

"drill a hole in it to take a pH probe"

 

[jrgilles]

"drill a hole in it to take a pH probe"

Do you have any experience with the 418? Does the maxijet recirculating pump do the job?

 

[lvsuckerfish]

the drip will be the same by the same I mean you will adjust the drip for the 75 or 125 or 240 what ever size tank you have) it just holds more media and will last longer is all. pm me I will give you a link to get a DIY probe holder from I have one but I plan on using it on my ca reactor it is a bulk head and probe locks into it with a screw on nut and seal inside to prevent leaks.... they are not a sponser on the site so I do want to go against the rules. as the whole free advertising. and not sure if the sponsers are able to get them.

 

[Myteemouse]

ooo shoot me that link too please!

 

[NaTe R]

The only problem i see with going with the 618 is that unless you have a heavy demand you will have to dial it down alot.

the 618 will want you to use a mj 1200 feed pump so you could blast effluent in to the system and the 618 would keep up no problem. but you are going to be doing a slow drip and therefore the chamber will have a tendancy to get CO2 bubble inside the chamber. I had this isssue with my 618 on my tank becuase i pulled out much of the bigger higher demand coral and replaced it with smaller frags and had to dial the 618 way back and had to fight with the air bubble i would get in the chamber.

My recomendation is go with the smaller one. cheaper, easy to set up for a system your size and dont worry bout if you upgrade these GEO's dont lose much value you can always sell it to sombody and go to the 618.

 

[Maxx]

Actually, I would suggest almost the opposite of NateR.

Not knocking him, this is just like everything else with this hobby: If you ask 4 people a question, you'll 5 answers on how to do it "best".

I'm running two Geo 612's on two separate systems. One has about 75 gallons total system volume, the other has about 170 gallons. Never had an issue with either one being run using a reactor designed for up to a 300 gallon tank.

NateR makes some good points, but I looked at things this way:

If you think you're going to upgrade to a bigger tank, at all in the future, buy the bigger Ca Rx now. Its cheaper and you'll go longer periods between refills.

You cant do that with everything in the hobby, (chillers & pumps for example) but this is one where throttling the effluent out wont hurt the reactor. And if you feed it like Don W suggests, (using a pump like an aqualifter which pulls water instead of pushing) then you dont have to worry about putting back pressure on the feed pump.

Nick

 

[jrgilles]

Sweet, thanks for the info.

Beaujames hooked me up with a sweet deal, so now I'm the proud owner of a Geo 612 and all the goodies it needs to run.

Beautiful piece of equipment. I have it all wired up now, but am resisting the urge to turn it on until after the thanksgiving break, since I'm about to go out of town.

It currently has a maxijet hooked up as a feed pump, but I'll check out the aqualifter too.

Beau had his running with a higher flow of effluent, and a higher pH in the reaction chamber, and seemed to like running it that way (more less concentrated effluent instead of dripping more concentrated effluent.)

I'll mess around with some options when I get back from break.

In the mean time, any advice on dialing this guy in would be appreciated.

Thanks for all the info guys! It helped me know what reactor to get, and thanks beau for a great deal on some wonderfully maintained gear.

 

[Maxx]

If he gave you the instruction sheets with it, you'll be good to go. If not, you'll have to wait a bit for me to go home, locate mine and get them scanned. I can then email it to you.

The 612 was very easy to set up and get dialed in.

Nick

 

[NaTe R]

Congrats jrgilles. I just looked for a thread on here were we went preetty step by step with someone who was setting up a calcium reactor not to long ago but couldnt find it.

one piece of advise i would give you is too research adding magnesium media to your new reactor. find out if it is right for you, It was right for me and i know of other people that have had success with it as well.

i havent ever herd of the aqua lifter as a feed pump idea that sounds like it might work pretty well.