RODI filter replacement cartridge advice

[Reefrats]

Hi! I'm new to reefing - just 6 months in. I have a Marine Depot 4 stage advanced RODI system. I make about 70 gallons of water a month. I'm on City water and the annual report is here: https://cdn.pompanobeachfl.gov/city/pages/utilities/Pompano-Beach-CCR-2019-Web-Version.pdf

I want to get on a schedule to proactively replace my filters and Aquarimate just told me to order new cartridges. Should I order the Marine Depot replacements https://www.marinedepot.com/marine-depot-ro-di-replacement-filter-kit ? Are they comparable to the BRS replacements? I'm thinking if I replace the prefilter, carbon, and resin every 6 months I will stay ahead of any problems and avoid the need to upgrade my system.

It looks like I entered the following in Aquarimate:
- prefilter - every 6 months
- carbon filter - every year
- RO memberane - every 3 years
- resin - every 6 months

Attached are photos of my system and the color changing carbon. I'm assuming I copied this schedule off someone on here. My water pressure on the gauge hasn't really changed - it is always around 65 psi, my tds in is around 100 and my tds out is 0.

Thanks in advance!

 

[SDK]

You have an inline TDS meter. Change the cartridges all at the same time when the TDS meter goes above 0. You are just wasting money if you change cartridges with a zero TDS reading.

Change the RO membrane when you see the "pre DI" TDS reading start to creep up, and you start going through DI resin faster than whet has been normal...

All of your RO/DI maintenance should be based on data and not a schedule for a small home user...

 

[K7BMG]

Changing out your consumables cant be put on a schedule.
Use the TDS meter to tell you when things need to be changed

 

[Reefer1978]

Here's my recommendation:

• prefilter - when it looks dirty. Yours looks filthy. Should be white. If you have that much sediment going into the hour, change it more often, or at least rinse it off well once in a while.
• carbon filter - every 6 months.
• membrane - when TDS starts creeping up.
• DI Resit - when it's exhausted. You have color changing resin, when it's all brown - time to change it.

 

[Reefrats]

You have an inline TDS meter. Change the cartridges all at the same time when the TDS meter goes above 0. You are just wasting money if you change cartridges with a zero TDS reading.

Change the RO membrane when you see the "pre DI" TDS reading start to creep up, and you start going through DI resin faster than whet has been normal...

All of your RO/DI maintenance should be based on data and not a schedule for a small home user...

The TDS meter came pre-installed. I have “in” and “out”. How do I figure out “pre-DI”?
thanks!!!

 

[Reefrats]

Here's my recommendation:

• prefilter - when it looks dirty. Yours looks filthy. Should be white. If you have that much sediment going into the hour, change it more often, or at least rinse it off well once in a while.
• carbon filter - every 6 months.
• membrane - when TDS starts creeping up.
• DI Resit - when it's exhausted. You have color changing resin, when it's all brown - time to change it.

I will pull it and check. I think it has always been that color.

 

[SDK]

The TDS meter came pre-installed. I have “in” and “out”. How do I figure out “pre-DI”?
thanks!!!

"In" is pre DI Canister and " Out" is the final TDS reading before the water goes into your container.

You want to check your incoming TDS and see where it is at with your RO membrane currently. Then check it periodically. Once the RO membrane starts to go, you will see that number start to rise fairly quickly.

Check the outgoing final TDS every time you make water. It should go down to zero after a few minutes of flushing. As long as it holds at zero you are good. Once it starts creeping up to 1 or 2, change your cartridges.

The best thing you can do to be proactive, is order the replacement cartridges now so you have them on hand when you need them. Then it's a quick 15 minute change when you need them . After you make the change, just order and stash another set away..

 

[K7BMG]

The TDS meter came pre-installed. I have “in” and “out”. How do I figure out “pre-DI”?
thanks!!!

Just move the first probe and have it after the RO and before the DI sections.

 

[Reefrats]

"In" is pre DI Canister and " Out" is the final TDS reading before the water goes into your container.

You want to check your incoming TDS and see where it is at with your RO membrane currently. Then check it periodically. Once the RO membrane starts to go, you will see that number start to rise fairly quickly.

Check the outgoing final TDS every time you make water. It should go down to zero after a few minutes of flushing. As long as it holds at zero you are good. Once it starts creeping up to 1 or 2, change your cartridges.

The best thing you can do to be proactive, is order the replacement cartridges now so you have them on hand when you need them. Then it's a quick 15 minute change when you need them . After you make the change, just order and stash another set away..

Thanks! I didn’t realize the “in” number would start to go up. I thought “in” was straight from the tap. If “in” is before the DI canister then how would “in” go up?

I will order and keep spares on hand for all 4. Right now “out” is always 0 but I let it run a bit anyway and usually remember to back flush. I will order an RO membrane as well and assume it will need to be changed around 3 years.
Thanks!

 

[Reefrats]

Just move the first probe and have it after the RO and before the DI sections.

Ah gotcha!

 

[K7BMG]

I have two three probe TDS meters on my RO/DI system.

I like to be redundant.
Just to make sure a probe has not failed me.

I have two probes on the source water input. (Probe one from each meter)
My TDS input is around 170 to 180 average. These are the only probes that have a discrepancy on the readings. TDS meter one is always 10 parts lower than meter two. Always...

After my RO I have two probes, (Probe two from each meter) typically at the moment the RO output is 10 from around 3 several months ago. This set of probes always agree.

This tells me the RO membranes are needing replaced, and I had the new membranes delivered yesterday for replacement this weekend. I would have to look back at my records but I think these membranes lasted 10 months, and filtered about 3-4 thousand gallons.

Two probes on the output or product water. (Probe three from each meter)
Always 0.