ph controllers and inline electrodes

[helgymatt]

I'm considering putting a pH controller on my 75 gallon tank. I was able to get a Milwaukee SMS122 cheap ($20) so I thought i would give it a shot. It does not have a probe so I'll need to get one. I was looking around at varoius probes: Neptune, Omega, Pinpoint, and Hanna. Since my system has bulkheads with a closed loop I thought it would make sense to install the probe inline.

I've been looking at these various inline probes.
Automated Aquarium Systems - Hanna HI1001 In-Line pH Electrode
General Purpose 1/2" MNPT pH Sensor
Industrial pH Instrumentation and Electrodes: Industrial Electrodes
All cost around $100.
Does anyone have any experience with any of these inline probes? Will they last longer than normal pH probes? Also will it be any problem to run this inline before my Panworld pump that pushes 700gph?

I know people say controllers are not necessary and solenoids on a timer are good enough. I have used solenoids on timers for 2 years and things have worked fairly well. I thought I would give the controller a try. In my 75 gallon tank, it seems like the pH is always much lower in the morning and then higher in the evening. I've started to see some BBA algae around my tank, which I figure is due to inconsistnet CO2, so I figure the controller would keep everything constant 24/7.

 

[shoggoth43]

No experience with the inline probes. However, 'm not sure I'd place the probe before the pump just because it's likely you'll get more of a buildup of crud if it's place before the filtration. I've seen the probe holders that go in the sump and that generally seems to work for most people who do that. Depending on your tolerance for "stuff" in the tank, you might be able to just pop a considerably cheaper probe in the upper rear corner just to try things out before you commit to a 100$+ item. Of course then you have an extra probe lying aroung that you may not need.

On a side note, couldn't you just up the rate of CO2 going into the tank? Assuming you aren't getting the amount of CO2 you want, I'd start there. Or is this just a case of wanting the same general readings throughout the day instead of the pH shift from morning to night? Either works, however to use the controller in the method you want, you're going to have to boost the CO2 output anyway to get the pH down.

-
S

 

[Gerryd]

Hi Matt,

I used to use the SMS122 and it worked well.

I ditched it as I like the argument against them in that since c02 fluctuates so much during the photoperiod that it is potentially delivering LESS STABLE rates of c02 due to the solenoid switching on/off more often. I added more surface agitation and the c02 is OFF when lights are OFF.

Plus, if the probe is not calibrated often you could get flase readings and not realize.

I now use a Hanna ph/temp meter, but no controller. Better meter/probe IMO than the SMS anyway........

So, only c02 is delivered when lights are on.

Also it is one less thing to be concerned about.........

I second the advice to slowly raise your c02 a bit and watch the bba.......it should first stop spreading and then the existing will recede as well. Manual removal helps

Just my thougts.

 

[helgymatt]

Thanks for the comments. I have a few replies to some of your suggestions.

#1 - If I buy a quality probe (i.e. not Milwaukee), I should be less concerned calibration issues, right?

#2 - I want to place the probe before the pump because I inject CO2 right after the pump. Placing the probe after the pump would only provide false readings caused by the recently CO2 injected water and not the "tank" water.

#3 - I think my CO2 distribution is the point where I am lacking...maybe not. I currently just inject it into my Ocean Clear filter. It all gets dissolved so I don't see how a PVC reactor would be any better. It seems I need a very high bubble count to get the CO2 where I want it during the day. Then at that bubble rate, CO2 get rather high by the end of the day and my rams start to hide out in all the plants (likely because of high CO2) and my cardinals also seem to have odd behavior - not schooling as well. So I turned down the CO2 a bit so I don't see this behavior as much, but then my CO2 concentration is not high enough for the first half of the day…..which I presume has cause some BBA recently (inconsistent CO2…).

I was looking at a controller so I can keep my same method of distribution, and have the controller keep things stable 24/7. Not this up and down cycle as the CO2 goes on and off with the timer and then throughout the day as the CO2 concentrations increase.

#4 I have tried mazzeis and I don't like them. Mine was loud, not working properly, and it is drastically affected by changes in pressures caused by my filter clogging and reducing flow.

I could consider a needle-wheel pump, but I'm not sure my current bulkheads can handle any more flow. I have 3/4" input and I'm already using a Panworld 100 (700 gph). Does anyone think I would have issues adding in a needle wheel to run parallel to my Pan World and Ocean clear? But then again, I will have a lot more flow to deal with in my tank and it’s already a whirlpool in there.

Maybe I'll just try SMS122 and throw a probe over the side of the tank and if it works out how I like it, I'll think about hooking it up to run inline. I could get one of those compression fittings for $6.00 to use it inline.

 

[Gerryd]

Hey Matt,

1. I think regular calibration is important no matter the probe. A more expensive one may be more accurate and sensitive and thus require MORE care/calibration.

2. Well the intake to the pump is going to have mostly the water that is closest to the intakes. this may or may not be a good thing.....I agree that it is better to be at the further end of the c02 as opposed to right after injection.

3. I think you need to add more SURFACE agitation to help introduce more 02 while the c02 is on... Then you can keep the good plant levels and not stress the fish.

I have the same issue in that I have a ridiculously high bubble rate count. I find that turning on my c02 at least 90 minutes prior to lights on helps my tank a lot. This gives the c02 levels a chance to rise in the tank before the lights come on. Maybe even lower the rate since the c02 is on longer in duration........

I see no issue with running a needle wheel pump in parallel with the rest of your setup. It is easier with a sump, but can be done. Just need to figure out placement of the NW pump and hoses...........

Later,

 

[helgymatt]

I disagree that a higher quality probe will require as much attention as lower quality ones, like the one that comes with the Milwaukee controller. I have no experience with either, but I have read many places that when users upgrade the probes they find they drift or lose calibration very little. Either way, I do think it is important to check them every few weeks, which IMO is very simple to do.

In regards to Oxygen concentrations...isn't it true that when plants are pearling the water is already saturated with oxygen??? I don't see how increasing surface agitation more could help....isn't it just going to drive off more CO2. There is already a fair amount of agitation.

And like you, I have the CO2 come on long before the lights - 2 hrs before.

The issue with adding a needle-wheel pump is that i'm not sure if my bulkheads can handle it - I don't want to starve the pumps because they can't get enough water through the bulkheads/pipe.

I think I'm maybe just being to anal about this. I can deal with a little inconsistency in CO2, but when it starts to affect the fish and bring on algae is when/why I got concerned and thought about a controller.