Newbie looking for feedback

[Myka]

Originally Posted by IanWR

I think the take away was that 1 30% change a month removes 30% of nitrates (for example), and an infinite number of infinitely small changes that equal the same 30% over a month would reduce it by just under 26%. So you do lose 4% efficiency by continual water changes, but gain consistency and possible ease of maintenance.

Sorry Ian, you misunderstand the article (or maybe you misunderstand what I was referring to). The article references continuous water change, as in you're removing old water at the same time as you're pumping new water in, not daily water changes.

I was referring to daily WC where the total WC volume is removed, then consecutively replaced. Since every time you do a WC you're removing a portion of the new sw you just put in yesterday it is less effective. If the OP chooses to do daily AND continuous WC (which could very well be the case If he's using a doser for it) that would compound it by another 4%.

[IanWR]

Originally Posted by Myka

Sorry Ian, you misunderstand the article (or maybe you misunderstand what I was referring to). The article references continuous water change, as in you're removing old water at the same time as you're pumping new water in, not daily water changes.

I was referring to daily WC where the total WC volume is removed, then consecutively replaced. Since every time you do a WC you're removing a portion of the new sw you just put in yesterday it is less effective. If the OP chooses to do daily AND continuous WC (which could very well be the case If he's using a doser for it) that would compound it by another 4%.

I don't think I misunderstood either you or the article. You suggested changing 2g a day was wasteful and weekly or biweekly was "much more effective". I disagree with that assessment (again, respectfully! 😀 )

The OP is talking about a 180g tank (let's assume for the sake of argument that the total system water is 200g). If they change out 2g a day they are doing about 60g a month, for a total of 30% water volume. If they did it all at once every month it would reduce nitrates (and any other accumulated pollution) by 30%. By changing 2g a day it is reduced by about 26% (per the RHF article). There has been a 4% waste, in this case 8g.

I don't see 8g of saltwater a month lost to be that big of a waste to gain the benefit of automating the process (plus stability benefits, plus not having to heat the new water).

I don't mean to derail this thread, just wanted the OP to hear that I thought the plan for using the DOS to change 2g a day was a good one (IMHO).

[Myka]

Originally Posted by IanWR

I don't think I misunderstood either you or the article. You suggested changing 2g a day was wasteful and weekly or biweekly was "much more effective". I disagree with that assessment (again, respectfully! �� )

Sure, but the article doesn't support your opinion then. The article refers to a single continuous WC, not a daily consecutive WC.

For a daily consecutive WC of 1% per day for 30 days you will have 26% new SW in the tank. For a weekly consecutive WC of 10% weekly for 30 days you will have 34% new SW in the tank. If you change those WC numbers to 2% and 20% you will change 45% and 60% over 30 days respectively.