Cycling - almost there, PH and Betta?

Hello all, regulars will know I made the rookie mistake of starting a fish-in cycle; misleading store advice and not a lot of research by me

Anyways, I feel I'm finally getting somewhere after 5 weeks of WC and testing daily- Yesterday and today with API Masterkit my tests are finally coming back with 0 Ammonia, 0 Nitrites, 0-5 Nitrates (I am assuming this is low as I have 5 different live plants).

Because I have been doing at least daily WC upon results of the tests:

1) It feels very unnatural to stop the WC; I'm paranoid I'm going to hurt the fish after all this effort by not changing, but realistically I can't WC everyday for the rest of my life! Is it okay to now test daily and WC as appropriate to the results? Is there a minimum period now to test, say 7 days? Then I can stop testing this tank and WC weekly?

2) PH has sat between 7.8 and 8.2 (7.8 after the WC and 8.2 prior)
So that's where I'm left. My water is very hard, we live on a chalk bed and again bad advice and lack of initial research by me means I have guppies and corys (Albinos and Bronzes). I have a large tank already purchased and last weekend was set up and a fishless cycle was started to move the corys over eventually - I will be purchasing RO water from my local aquatics shop to mix with tap water once cycled but this will be a gradual process as I don't want to shock the corys when I move them to the new tank.

The results for my PH are:
Tap - Low 7.2 High 7.8
Tank (today) - Low - 7.6 High 8.2

Lastly, in time I would like a Betta tank. I've seen a 30L which would fit perfect in my house and I would plan to RO and tap water this one too. Is this the right route?

I just hope I'm doing everything right and to the best of my ability?

I would test daily until you are certain ammonia and nitrite are staying at zero, but only do a water change if either of them read not-zero. Then go to testing every 3 or 4 days, then once a week. Once you are sure the tank is cycled, you only need to test when you remember or if the fish start acting oddly.
Once the tank is cycled you need to change at least 50% of the water every week. This removes nitrate and all the other things we can't measure which build up. And water changes replenish minerals etc which get used up between water changes.



For a betta tank, that sounds perfect, and yes with hard water mixing with RO is good for a betta.

Sounds like you're making all the right moves now! I use RO water too, and haven't bit the bullet and bought my own set up. I went to Walmart, bought 5 of the 5 gallon refillable water jugs (the ones for water coolers), and now I refill them for 1 buck at the local RO filling station near my house. I get 25 gallons for less than the LFS charged for 2.5 gallons. Just a thought.