Controller testing and dosing station experiment - Controlling salinity with my Apex

[innovusaquaculture]

I've added a couple 10 gallon tanks plumbed on my return manifold for a new probe and testing tank and a dosing tank. I currently have 3 of my 4 display tanks connected to this main system. I have two other tanks that are cycleing and will have every last thing quarantined before entering that system. This main system will eventually go through QT and be fallowed for 76 days and join the other system, so all the tanks in my office will be in one large system.

Here are the reasons:

1. I'm tired of probes getting dirty with gunk in the sump. I'm adding a pre-filter to the water coming into these tangs to filter large particulates that may be returned from the sump to the systems. This should not effect anything I want to test for in the Trident and Apex probes.

2. These are up on a higher shelf and the probes and Apex Trident can be more easily maintained.

3. I can dose to a controlled environment that I can provide very high mixing flow without possibly effecting readings in the rest of the sump. Now there is still going to be slight spikes as the doses get returned to the tanks, but since the mixing tank gets returned with to the same location as the tank returns it will be fairly UN-substantial.

4. I cleans up a lot of equipment in the sump.

5. It add water volume and aeration to the system.

6. It is my hope to be able to build a redundant top off system based on salinity, not water level. This means multiple salinity probes and lots of Apex programing.

Anyway I will try to keep this tread updated with the progress of this experiment.

 

[nezw0001]

Interesting solution. I'll be interested in how you solve for inconsistency in the salinity probe.

 

[innovusaquaculture]

Interesting solution. I'll be interested in how you solve for inconsistency in the salinity probe.

Yes, that is going to be a challenge. I'm working on that one! First is to get a second salinity probe and see what the variations are. BRS is out of the modules right now, so I'm waiting for them to come back in.

 

[Tastee]

I have been able to get very stable readings from my salinity probe in my RSR 525XL. I was able to route the cable along the top of the sump area well away from all other cables (which I route along the back wall) to avoid electrical interference. The cable only comes near other cables when it gets into the equipment cabinet side and connects to the Apex head unit. Here is an example graph.

On my smaller RSR 250 where space is more cramped I can’t get anywhere near as stable a reading. This is entirely due to electrical interference as I know the salinity in the smaller tank stays just as stable as the larger tank. This may help you in your installation.

 

[innovusaquaculture]

I have been able to get very stable readings from my salinity probe in my RSR 525XL. I was able to route the cable along the top of the sump area well away from all other cables (which I route along the back wall) to avoid electrical interference. The cable only comes near other cables when it gets into the equipment cabinet side and connects to the Apex head unit. Here is an example graph.

On my smaller RSR 250 where space is more cramped I can’t get anywhere near as stable a reading. This is entirely due to electrical interference as I know the salinity in the smaller tank stays just as stable as the larger tank. This may help you in your installation.

That is also one of the reasons for the testing tank. Since the probes are now located in a separate tank with nothing else I can run the probe cables by themselves to the APEX head unit or modules completely away from any other electrical wires.

I'm also going to experiment with adding ferrite o’rings ( i.g. ) to the salinity probe cable to see if that will stabilize the reading as well.

Here is a reasonable article on electrical induction that will reference ways to stop induction into control cables like the salinity probe: https://www.smar.com/en/technical-a...ize-their-effects-in-industrial-installations

 

[innovusaquaculture]

I've been so busy I haven't had time to post the latest to this build experiment.

The main testing tank is on the right. All the testing for the Trident and main base unit probes are in this tank. There are no micro bubbles in this tank it is fed from the return manifold from the sump. The dosing/mixing tank is on the left and is fed from the testing tank and returns to the sump.

The theory is that I am testing and monitoring exactly what is being returned to the tanks so I have time to react in dosing at the micro level.

I've added the second Salinity probe to the mixing tank and the top off pump from the RO reserve below.

Here is the APEX program for the Top Off Pump:

Fallback OFF
If Salt02 > 35.1 Then ON
If Salt02 < 34.9 Then OFF
If Salt < 35.0 Then OFF

The "Salt" probe is in the testing tank and the "Salt02" probe is in the mixing tank.

As it turns out with this setup there is far lest APEX programing than I thought there would be.

I'll be adding a water level to the sump as a backup so if the water level in the sump gets too high it will shut down several things, including the Top off Pump. That will add additional redundancy.

So far this system has been running for 3 days flawlessly.

 

[innovusaquaculture]

BTW - a lesson on drilling cheep "dollar per gallon" 10 gallon tanks: If you tighten the bulkheads too much the glass will crack!

I had to repair one of the glass panels in the testing tank because I cracked it. I just sandwiched the crack from top to bottom between two new pieces of glass with silicone. Pretty is not important, function is!

 

[innovusaquaculture]

Update -

I've found that the conductivity probe in the dosing tank runs 1 point higher then the testing tank.rather then re-calibrate the probe, since it is consistent I've decided to just adjust the apex program. The advantage to this is I've been able to move the salinity consistency in the sump to within .2 variance over a 24 hour period. That translates to immeasurable in the tanks.

Here is the new Apex code for the top off pump:

Fallback OFF
If Salt02 > 35.1 Then ON
If Salt02 < 35.0 Then OFF
If Salt < 35.1 Then OFF
If SmpMax CLOSED Then OFF

(I did add the Sump Max switch as a backup, in case the conductivity probes fail for some reason)

Note that Salt02 will typically run at 36. When Salt hits 35.1 then the top off pump dumps about a ~1 gallon of fresh water into 5 gallons of salt water. It drops Salt02 to ~30 and turns off the top off pump. That mixes and dumps into the sump over the next ~30 minutes. It drops the salinity returning from the sump, which has a volume of ~30 gallons, by ~.2. That is then mixed to the rest of the 250 gallon 3 tank system at a rate of ~5 x turn over per hour.

This is exactly what I wanted to do with this entire experiment. Everything drastic that happens now happens on a very small volume of water (5 gallons) in a 250 gallon system, is then mixed into a constant larger volume of the large system, then tested and then dosed again. 24 hours a day. It is the ultimate averager.

I have struggled to figure out how to be consistent with my tanks. To develop a routine that works for me. One of two things have happened over the last month of this experiment. Either my tanks have started to come into their own and corals have all of a sudden started to like their environment and look better or the new stability this system has provided has been working. (or it could be something else, life is a mystery after all).