I have a 6x2x2,a 48x18x21(odd size),A 30x18x18,a 36x18x18,two 18 cubes and a regular 36x12x15,so not that many really compared to some people on here

On the 4x2x2 I do 2 partial water changes a week of about 40-50% using reject water from my RO unit. I use a hose and pump to do this so I just sit back with a cup of tea and observe whilst watching the telly takes about 45 minutes I set the hose up to water the garden as well so 2 jobs in one!

My 3x2x1.5 marine tank has a 20% water change every week once I have the mixing bucket filled with RO water which takes about a day sometimes more I can do a water change within about 30 minutes using hose pipe and pump.

My 150 litre small fish community tank gets a 35-40% water change once a week using reject water from my RO unit this takes half an hour because I do it manually siphoning water into a bucket, although the water is pumped back into the tank using a small eheim sump pump.

I store all of the reject water from my RO unit in 2 x 225 litre water butts in the garden the reject pipe is fed through a small hole I drilled in my kitchen wall and goes in the top of one of the water butts and the two butts are joined together. I use a pond pump to pump water into my tanks directly from the water butts.

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Alan

Thweeerp!