Cycling new tank, TDS getting higher, ph staying same with Fluval

[Jenbenwren]

The new tank for our RCS has been cycling for 3-4 weeks now and today it was at ph7, ammonia 0, nitrite barely registered, nitrate 60, gh8, kh6. The TDS is 701ppm! WT...?Higher than last time I checked (536ppm) when it was very cloudy and I've been running 2 external canisters in it for the last 3 days, 1x300lph & 1x800lph! The water is clearer than our community tank as well and it hasnt had a filter in it for 3 days and it's at 108 ppm! How can I lower the TDS?

Once I finish planting I'll do another small water change without adding kh powder and less aquarium conditioning salts and have it tested once more before I move the RCS in. We have fluval shrimp stratum in it and I thought it lowered ph but it hasn't. Our tap water is around 7ph and so is our community tank.

Will it take longer for the fluval to affect ph, or is there a small amount of something else I should add that's similar to the fluval to lower the ph a bit more? Our kids have their hearts set on adding some crs or cbs (will the crs & cbs crossbreed, as they are basically the same shrimp just different colors, muddying the colors of their offspring) but the water parameters still aren't right for them yet.

[Jenbenwren]

I've since learnt I was right not to put cbs & crs in the same tank, I just wanted to make sure.

I've just checked the TDS from our kitchen and laundry taps its 30 ppm for both, and both tanks still have the same TDS.

I can see in the smaller cannister filter (it's see through) and the filter wool and sponge are black ( I only added the filter wool and rinsed the sponge 3 days ago), and the ceramic stars are pretty dirty as well, so I'm tipping the larger one is pretty bad to. They are so grotty from all the finer particles of fluval being stirred up as I've been moving things around in there. I'll replace the wool and rinse the sponges and new filter wool in the water I take out if the community tank as it's due for a wc today or tomorrow and depending on how bad the ceramics are, I may give them a quick dunk too.

[Squiggle]

Your nitrates are very high, should be <5ppm, this will be contributing to you high TDS too. Doing a WC with your water will drop both the nitrates & the TDS, this is the only way to drop these two parameters. You should really be using salty shrimp to remineralise you water to the correct TDS before WC's, this will ensure you have the correct minerals in your water. If you intend on keeping crystals & you are using Fluval stratum then you should use Salty Shrimp GH+ as this will be best suited to your shrimp & substrate. If you are going to clean your filter then only do it in tank water as this will keep your bacteria & help keep the tank cycle going. :encouragement:

[Jenbenwren]

Awesome thank you. All the water parameters are great now and my next question was going to be should I being adding any sort of minerals to the tank. :-)