RO/DI Tap Water Mix

[matthew xia]

Hello - I'm about to do my first water change on a cycled tank (no fish yet). (First time fish keeper).
Our water is basically liquid rock so I'm going to be mixing 50% RO/DI water with 50% tap water.
I want to also add some sort of dechlorinator to the tap water (aquasafe etc) - my question is when do I add the aquasafe, and how much? Only 50% of the expected amount? Or a full dose for the total of water added regardless of RO/DI?

I hope that makes sense...

Thanks!

 

[seangee]

If you have the water in separate containers only treat the tap water. If the mix is in one container treat for the full amount.

 

[matthew xia]

Thanks Seangee.

 

[Byron]

If I were doing this, I would first run the tap water in the "mixing" container, add dechlorinator for that volume, then add the RO water. This will ensure the tap water is dealt with (it is instantaneous), and the RO will then dilute the conditioner which means less chemicals getting inside the fish. Then pour/siphon the mixed water into the tank.

 

[matthew xia]

Thanks Byron, this is great! I'm doing a 100% water change as I type with RO/DI and Tap mix. Because I don't currently have a fish I've just poured two buckets full of dechlorinated tap water into the tank, and am now working towards adding two buckets of RO/DI which should get me back to full (or near abouts)... I've never been so excited about testing water! Honestly - I'm really looking forward to the results. (and thank you also for the instantaneous answer... I did wonder).

Once we have a fish and I'm doing my weekly 25% - 50% changes I'll have stored 25 litres of RO/DI so will be able to use your suggested method of treating tap water, then adding the RO. Thank you so much.

 

[Martyn87]

I would really recommend for a first time keeper not to go down the RO route for your first tank. RO water can be expensive and it adds alot of time getting it unless you have a built in unit. I would really go with keeping hard water fish and there are loads of good cichlids you can keep if your water is that hard! If your still adamant next time then setup a second tank!

 

[matthew xia]

Thanks Martyn - too late I'm afraid - we have a RO unit so can make RO (this was meant to be a cheap gift for my child and has become a rather expensive hobby quite quickly). The plan long term is to get it installed permanently (it's a Vyair system that currently I have to screw onto the washing machine feed each time). And also planning to have a couple of 25 litre bottles in the yard for changes (so time consumption is minimised). Honestly though, thank you.... all the learning I'm doing here is great.

 

[Martyn87]

As long as you have an RO unit it is a lot easier but it'll be a chore when the tank gets bigger...and they always do!

But if you do have the commitment for it then you'll have some great fish options open to you!

 

[seangee]

Thanks Martyn - too late I'm afraid - we have a RO unit so can make RO (this was meant to be a cheap gift for my child and has become a rather expensive hobby quite quickly). The plan long term is to get it installed permanently (it's a Vyair system that currently I have to screw onto the washing machine feed each time). And also planning to have a couple of 25 litre bottles in the yard for changes (so time consumption is minimised). Honestly though, thank you.... all the learning I'm doing here is great.

That's easy if you have the space. For my DIY setup I got a brass Y splitter for the washing machine tap and drilled a small hole into the end bung where the washing machine outlet goes for the waste water. You can get an adaptor to go from a standard tap to 1/4" tubing. Try not to leave it in the sun, algae does manage to grow even in RO water , and it will mean extra heating effort in Winter. If you have a 50GPD membrane next time you change it buy a 100 or 150GPD replacement. I swapped my 50 for a 100 and now it takes half as long to get the same amount of water. Quality is identical. Next time around I will be trying the 150. I always refill immediately after the water changes so I am always ready in case of emergency.

Here is my stash for the weekend

Well I do have 3 tanks and they get 100% RO

 

[matthew xia]

Thanks Seangee - great tips - in that case I'll be leaving it in the cupboard under the stairs! And the tip about refilling as part of the water change makes so much sense - I'll be doing that too. I'm not sure I completely understood this: drilled a small hole into the end bung where the washing machine outlet goes for the waste water. You can get an adaptor to go from a standard tap to 1/4" tubing. - I almost understand it - to, run the red tube (waste) off, you sent it back through the washing machine waste? How do you ensure there is no leakage? I'll certainly look into a higher capacity GPD - it's mighty sloooooow at the moment.

 

[Retired Viking]

I also use RO and buy it in 5 gallon containers so yes it can be a pain, trying to talk the wife into buying a RO unit to save me time running for water. I also treat the tap water first then add the RO.

 

[seangee]

Thanks Seangee - great tips - in that case I'll be leaving it in the cupboard under the stairs! And the tip about refilling as part of the water change makes so much sense - I'll be doing that too. I'm not sure I completely understood this: drilled a small hole into the end bung where the washing machine outlet goes for the waste water. You can get an adaptor to go from a standard tap to 1/4" tubing. - I almost understand it - to, run the red tube (waste) off, you sent it back through the washing machine waste? How do you ensure there is no leakage? I'll certainly look into a higher capacity GPD - it's mighty sloooooow at the moment.

These should explain. I never used anything that cost more than a few quid off Amazon and zero plumbing required. Leakage for the outlet is good old fashioned gravity - water can't flow uphill. All my tubes are white

Washing machine and RO unit are both permanently connected.

 

[matthew xia]

I also use RO and buy it in 5 gallon containers so yes it can be a pain, trying to talk the wife into buying a RO unit to save me time running for water. I also treat the tap water first then add the RO.

I really didn’t want to have to get one, every extra expense seemed like it was testing my love for my child!! (The initial purchase of a tank and two now dead orandas was for her birthday) - then determination kicked in, so we got the heater, then the testing kit, then the ammonia, then the almond leaves etc - for what it’s worth - I ended up spotting a deal online and think I paid about £35 for the Vyair unit (which seemed crazy and less than half the price I’d seen elsewhere). We’ll also have to see what effect it has on our water bill!

 

[matthew xia]

These should explain. I never used anything that cost more than a few quid off Amazon and zero plumbing required. Leakage for the outlet is good old fashioned gravity - water can't flow uphill. All my tubes are white
View attachment 102489View attachment 102490
Washing machine and RO unit are both permanently connected.

Thanks Sean - this is super clear! My next challenge!