Dechlorinating an auto water change system

[Cleveland M]

I'm thinking about adding an auto water change system to my rack but not sure how to dechlorinate the water. 

I've watched a ton of Cory's videos but have never seen this discussed.

How is it done?

[KBOzzie59]

The easiest would be to use a catalytic carbon filter.

 

[Wrencher_Scott]

Does it change so slow that chlorine is not a problem? It would scare me to not filter it though. 

[nabokovfan87]

On 9/17/2022 at 1:07 PM, Wrencher_Scott said:

Does it change so slow that chlorine is not a problem? It would scare me to not filter it though. 

Hard to know it's working when it isn't also.... it might be fine, but you will need to keep up on when to change the filter just to be on the safe side.

Question for me would be what exactly is the setup.  Overflow? Water in --> Water out?  Are you draining a tank, then filling it without having to move a python around?

You can setup a dosing pump for dechlorinator on a schedule.  There is some risk, but that's what that setup would be to get rid of filtering the water.

Option 2 would be to use a tank, pump the water from that holding tank and precondition the water as opposed to running it from the plumbing directly.

Edited September 17, 2022 by nabokovfan87

[Wrencher_Scott]

On 9/17/2022 at 1:53 PM, nabokovfan87 said:

Hard to know it's working when it isn't also.... it might be fine, but you will need to keep up on when to change the filter just to be on the safe side.

Question for me would be what exactly is the setup.  Overflow? Water in --> Water out?  Are you draining a tank, then filling it without having to move a python around?

You can setup a dosing pump for dechlorinator on a schedule.  There is some risk, but that's what that setup would be to get rid of filtering the water.

Option 2 would be to use a tank, pump the water from that holding tank and precondition the water as opposed to running it from the plumbing directly.

yes, option 2 would be the safest by far. 

[Cleveland M]

On 9/17/2022 at 3:53 PM, nabokovfan87 said:

Question for me would be what exactly is the setup.  Overflow? Water in --> Water out?  

Overflow water in/water out. 

Reading the options I think I'll probably go with the filter for the following reasons.

1. Treating a prefill tank  would require a tank  that's taking room that could be a fish tank. 🙂

2. Dosing pump seems slightly risky as there wouldn't be a notice of failure unless I either noticed it not running or that the fish were in trouble.

3. Since I know about how much water I would run through the system and how long the filter is rated for, I could just subtract a 10% safety factor and schedule the changes.

[TOtrees]

I cut a T in my cold water line, that is the source for my water change system. In that line installed a whole-house carbon filter in the line that supplies water to the tanks.

There is an inline timer valve between the filter and the emitters that sets when and how long water is added to tanks. 
I also installed a T right after the carbon filter that allowed me to add a dedicated tap at the sink for dechlorinated water. It’s great for rinsing sponges, manual water changes and etc. 

It’s not shown on the pics, but I also have a shower type temp mixing valve before the filter, with an optional cold-only bypass, so I can choose whether the dechlorinated water to the dedicated tap or the tanks is temp-specific or straight cold. 
It works great for me, highly recommend something like this for any water change system. 

[TOtrees]

Sharing a couple more features (suggestions):

The tap I added has Gardena quick connects and I can fill tanks directly from this tap via a Python hose that attaches using the same Gardena connectors. The tank end has a home built part using 1/2” cpvc (which unlike 1/2” pvc is sized to fit 1/2” sharkbite-style parts like the blue-handled valve shown in the pic). 
FYI Gardena’s 1/2” hose repair parts fit the Python hose perfectly, and the Gardena parts are a massive improvement over the connecters that come with the original Python (which are far and away the weakest link in an otherwise great system).