I am about to redo the filtration on my 120 planted rainbow tank from scratch. I *want* to ditch my two Eheim 4+ 600s in favor of one strong external pump (that will branch off to various returns for flow purposes) and a Nu-Clear mechanical (with option for carbon or Purigen) filter.
QUESTION: In our planted tanks, with (in my case, 2 of) black blasting sand covering my 18 x 60 footprint, do I need a BIO filter? The Nu-Clear would be an outstanding mechanical filter, powered by a strong external DC pump, where the retur flow is branched with ball valves three ways: 1) run with an inline Vecton 2 600 UVS, and 2) provide flow to my CO2 cerges and 3) boosted flow throughout the tank.
In this plan, there would be no biological media in a filter. The sand would house the biological bacteria needed to control ammonia. My tank is mature: its been running since May of this year.
Anyone do this currently? Anyone go without biological media and just use their sand for that? (I feel like someone said they did...)
take the media out of the filters , bag it up in a well rinsed /de-chemicaled or ideally new rinsed laundry bag (those drawstring permeable sack things) or similar permeable bag and place it in the tank.
next add new foam to the filters for mechanical scrubbing then run it and monitor levels, if all still tests good after a day or two start removing the old media in stages , eventually you'll either have two mechanical only filters and the tanks bacteria coping or you've hit spiking levels and abandoned the idea and put all the media back into your filters , either way you got a definitive answer at that point.