Probe Placement in my Sump

[olson2886]

Hey all - I've been running a tank for about 2 years now and am considering adding a controller (likely GHL). I have read several threads regarding placement of the probes, but I wanted to toss out the question for my specific build. I used a baffle kit and a 10g Petco aquarium. The first chamber is where the water enters (no sock) and the skimmer is located. It's pretty full and there are a lot of bubbles from the water flow (I know, bad for some probes). The second chamber is a large 5g refugium with sandbed, marine pure blocks, and chaeto. I presume the algae growth in this chamber would be prohibitive. Lastly, there is a small section with some sponge filters and chemipure, which leads down into the last chamber which contains dosing tubes, the heater, and the return pump. I don't love the probes being in the same chamber as any of these things.... but it seems to be the least worst place. Any thoughts or ideas would be appreciated!

 

[blaxsun]

The only real option is the section with sponge filters and chemipure, because you'll want to ensure a constant water level for the probes.

 

[olson2886]

@blaxsun Im not really sure that's an option unfortunately - not enough room. But the water level in that chamber matches the return pump anyways... it's not even it's own chamber but more of a subsection of the return pump chamber. The water level is constant aside from when the return pump is off, which affects all sections of the sump. Does it really matter that the water level will rise up from time to time (when I turn off pump), so long as it doesn't ever drop? I was more concerned about the swings during dosing than water levels, but I've never used probes so maybe im not thinking about every angle.

 

[blaxsun]

@blaxsun Im not really sure that's an option unfortunately - not enough room. But the water level in that chamber matches the return pump anyways... it's not even it's own chamber but more of a subsection of the return pump chamber. The water level is constant aside from when the return pump is off, which affects all sections of the sump. Does it really matter that the water level will rise up from time to time (when I turn off pump), so long as it doesn't ever drop? I was more concerned about the swings during dosing than water levels, but I've never used probes so maybe im not thinking about every angle.

It depends on the type of probes. Some need to be continually wet and others can't or shouldn't be immersed beyond a certain point (usually the cap/wire).

 

[olson2886]

@blaxsun Got it, thanks. Do you know if this typically depends on the function or the probe, or the brand? Hoping there is a whole brand that can be submerged.... ill need to do some research.

 

[blaxsun]

@blaxsun Got it, thanks. Do you know if this typically depends on the function or the probe, or the brand? Hoping there is a whole brand that can be submerged.... ill need to do some research.

Both. Temperature can be wet or dry, salinity needs to be rinsed off before drying (to avoid residue buildup) and ORP and pH need to be continually wet. None should see the water level extend to the underside of any cap nor up the the wires.

 

[olson2886]

Both. Temperature can be wet or dry, salinity needs to be rinsed off before drying (to avoid residue buildup) and ORP and pH need to be continually wet. None should see the water level extend to the underside of any cap nor up the the wires.

Thanks, I'm glad I posted before purchasing.... going to be a little more complicated than I thought. Honestly not sure what my options are now. Would chaeto interfere with any of them (not to mention potential algae growth on the probes)? Fuge starting to sound like a better option given that the water level only fluctuates about an inch. Or splitting the probes up across different chambers depending on their limitations. I had read that you can totally submerge salinity and temp, so was thinking those could get tossed in with the return since the water is motionless there which is needed for salinity. It sounds like the wires can get brittle over time, but this can take years and often probes should be replaced by then anyways? And then I could put Ph and ORP in the first chamber with all the bubbles as long as the top wasn't submerged? Im sure I am off on what the probes can or can't do.... but hopefully on the right track.

 

[blaxsun]

It would definitely not be a good idea to place in the refugium, no. Chaeto can get really slimy and I think the probes will get gummed up pretty easily (more than the chamber where the overflow empties into).