Safe water fiter to add directly into the tank?

Is there & can you recommend to me a water filter I could use to add water directly into the tank between larger water changes?
I have a 400G tank. I am on city water - they only use chlorine in my area. I don't have the report handy but I have it.
I have a demanding work schedule which will not allow for large daily or even every other day water changes.
I do have the tank plumed with a drain valve at the top for a constant drip system that never came to be.
I was looking for a filter I could use to add water directly to the tank for an hr or two on days I could not do regular water changes.
I figured the fresh water infusion would be better than Nothing. I am assuming that the filter will flow at a slow rate so the heaters will have time to adjust to the incoming water.
Not sure If I am explaining what I am looking for clearly? My worries are that some filters pull to much out of the water and some you just don't know when they stop working properly without testing them.

SO - sorry for the Long post. I know nothing about water filters. Anyone got a reco on something that Might fit the Bill here?
Thanks a Bunch

I have no answer to this but this is really interesting. I hope someone figures this one out.

If you just have chlorine in the water it will gas off in 24 hours. In this case, you could even ask the question - do I need an additional water filter?

Of course, if you are looking to remove the dissolved chlorine you could always run it through a bunch of carbon filters since that will remove the chlorine immediately.

However, a simpler solution could be to store a large amount of water in a holding container (I use a commercial-grade brute trash can, but I've seen folks use farm-style water storage containers), aerate and heat it, and then use a dosing pump to pull water from the bottom of the container and into your aquarium. You could set these dosing pumps up such that they just slowly and continuously drip water all day long or (since they're programmable through WiFi) pull a lot of water over the course of an hour or two. The only thing you'd want to be wary of is if you're heating the water that the container would run dry. Using the slow, continuous method for all day water the amount entering at any one time would be negligible in the total volume of water you have.

This tank is in my home office. I have a Rubbermaid drum but I would need several to do a water change. I certainly don't want to have these things lined up in my office every day. A commercial grade container is a consideration but where would I store it is the Issue? Again cant be in the house. No really gona work outside where the tank is located as that's the front of my house. I had carbon filters and never used it because not sure how to tell when its no longer effective?

I think RO strips to much stuff out the water right?

Is there nothing that could just exhaust directly into the tank?

They make chlorine test strips that would allow you to test the water as soon as it comes out of the filter(s) to see if it has been effective or not.

An RO unit would be fine - it just depends on how much water you are "topping off" and whether that will be a small enough volume of water as to not affect your water's chemistry. If you're only topping up like 10 or 20 gallons due out of the full 400 gallon volume due to evaporation, topping up with RO water shouldn't be an issue (you're only adding 2.5-5% of water back). If you want to the RO system to replace a water change system, it would be easier to make determinations on whether an RO unit would be feasible if we also knew your water parameters such as pH, GH, and KH so we can have an idea of how far off your water is from "pure".

I just looked and I don't have my Last analysis sheet - so I will have to request one from the water company.

I do plan to do regular water changes outside of this system. But because of my work schedule - I will probably only be able to do 2 changes a week.
The intent for this system is Not top off. Its to do a short run of constant drip daily. SO maybe one or two Hrs a day just run and let the overflow take care of the access.
Basically a constant drip that only runs a few Hrs a day??? I guess

A constant drip is fine - it's not as good as an actual water change, but is better than nothing for sure. It's just hard to know exactly what "1-2 hours a day" would equate to in terms of actual volume. 1-2 hours running an RO unit is going to typically be a very small volume of water - most hobby-grade RO systems only produce at most 150-200 GPD (gallons per day). At the highest range of 200, only running for 2 hours would equate to only about 17 gallons of pure water. At that small amount I doubt it is going to cause any adverse issues regarding pH or anything else, especially with larger water changes twice weekly.

I have not done any Research into RO units. If it runs that Slowly I don't think it would even be worth doing it for only a few Hrs a day.

Looks like I need to research info on RO units. Also seems like it would need to run at least 1/2 the day if not the entire day to have any actual affect on the tank.
I just don't know what that will do to the PH or anything else. Thanks so much for the responses.

Guess I am moving back into the constant drip Arena. With that slow a flow temp should be a none issue. Not sure about the water Parameters

doing more research - Thinking Maybe a HMA filter might be a better fit for me

I use a "WODER WD-10K-DC" under sink filter in line on my fill hose hooked to my sink tap. Using since 2017. Refill my tanks at a slow rate, add Seachem Prime after they are topped off. There is learning curve pertaining to your tap water. Maybe not the ideal water change method for a discus tank, but it works for me with my tight schedule. I can't seem to stop my fish from spawning.

You add the Prime After its topped off?

I talked with bulk reef a lot and I think I am going to assemble a system with parts from them!

I want my to run non stop - Constant drip, 100G a day

Yes, I add at he end. It just works for me that way. It's always been a dream of mine to have a constant flow system for my tanks, but they're all in my house, not a dedicated fish room.