Substrate help!

[chompchompdie]

I have a small aquarium up and running with a lava rock substrate. I have recently been itching to plant the aquarium, but the lava rock seems like it would be an unsuitable substrate for a planted tank. I would like to switch to a laterite/ small gravel mix. What would be the easiest way to make the switch? Should I transfer the fish to a large bucket while i do the work? Is there some magical-secret technique to doing a substrate change with the fish in the tank? And will removing the old substrate seriously compromise the biological filter of the tank? Thanks in advance for your input!

 

[Avalon]

Yes, lava rock is unsuitable for a planted tank. It's really good for a fish only tank because the porous rock allows for much more surface area for bacteria, if you can keep it clean.

To make the switch, drain most of the water out. Save a bucketfull for your fish while you make the swap.

Remove filter, heater, and all decorations. Place filter on bucket if it will fit. If not, no worries. Just don't let it dry out. The filter will keep your tank from re-cycling. Do not clean any part of the filter, nor change filter cartriges. Remove fish.

Empty everything else out and clean tank with water only. Dry. Then add laterite and gravel (or Flourite if you wish). Add water so it covers the substrate by an inch or 2. Plant your plants. Fill the rest of the tank, saving room for water in the bucket. Add heater and filter. If your water is not around 78F, let the heater heat it up. Use the water in the bucket to fill up, as well as the 'plop' method to put the fish back in so you don't have to net them again. Skim any leaves & particles off the top with net and you are done.

Total time: 2 hours.

 

[Avalon]

I forgot about the biological filter thing. You will lose bacteria, but keeping the filter intact is the most important part. I've done lots of tanks this way, and I've never noticed a problem. If you have a large fish load, your tank my go through a mini-cycle. If you have just a few fish, you may not even notice a mini-cycle.

Just in case, save some of that lava rock in a separate container with the old tank water. You can use this rock in the container in your fishtank for a week or so, just to make sure your tank won't cycle. Make sure to check Ammonia and Nitrite readings daily for a week.

 

[chompchompdie]

Thanks!

Thanks for the reply....that dosen't sound too bad. I'm a little worried that installing laterite will cloud the water and make life difficult for the fish. Should this be an issue if i'm careful?