# Dada2 denoise - why do I have so many reads filtered out

**URL:** https://forum.qiime2.org/t/dada2-denoise-why-do-i-have-so-many-reads-filtered-out/8534
**Category:** User Support
**Tags:** dada2, filtering
**Created:** [February 26, 2019, 8:05am UTC](https://forum.qiime2.org/t/dada2-denoise-why-do-i-have-so-many-reads-filtered-out/8534 "2019-02-26T08:05:21Z")
**Posts on this page:** 1
**Showing post:** 8

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### Author: ![Jo\_mee](https://forum.qiime2.org/user_avatar/forum.qiime2.org/jo_mee/32/3030_2.png) [@Jo\_mee](https://forum.qiime2.org/u/Jo_mee)
#### Post date: [March 4, 2019, 8:52am UTC](https://forum.qiime2.org/t/dada2-denoise-why-do-i-have-so-many-reads-filtered-out/8534/8 "2019-03-04T08:52:41Z")

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I see..but I still have doubts. Please check the results of default setup (Q2)

| sample-id | input | filtered | denoised | merged | non-chimeric | % left |
| --- | --- | --- | --- | --- | --- | --- |
| #q2:types | numeric | numeric | numeric | numeric | numeric | |
| LB17-16-001 | 145783 | 123434 | 123434 | 68005 | 45408 | 31.15% |
| LB17-16-002 | 70462 | 60081 | 60081 | 31014 | 22621 | 32.10% |
| LB17-16-003 | 119707 | 96946 | 96946 | 73652 | 30813 | 25.74% |
| LB17-16-004 | 130350 | 112151 | 112151 | 61758 | 42091 | 32.29% |
| LB17-16-005 | 111168 | 95150 | 95150 | 50107 | 35143 | 31.61% |
| LB17-16-006 | 122771 | 99810 | 99810 | 68519 | 38149 | 31.07% |
| LB17-16-007 | 119037 | 100004 | 100004 | 60282 | 34820 | 29.25% |
| LB17-16-008 | 105227 | 83766 | 83766 | 51094 | 24924 | 23.69% |
| LB17-16-009 | 203605 | 171129 | 171129 | 85039 | 50089 | 24.60% |
| LB17-16-010 | 143034 | 121132 | 121132 | 105902 | 44471 | 31.09% |

Is it a lot?

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