Adding An Extra Filter, Any Issues I Might Get

[DaveA76]

as stated on title, i got a 55gal malawi mbuna set up and its currently running a fluval 305 and a fluval 3+, but have just bought a new 2000lph external to run along side the 305 and then remove the 3+, could i expect any issues with the water until the bacteria has built up in the new canister as im well stocked as you would expect with a malawi set up and want to be prepared before installing it
 
thanks
dave

 

[DrRob]

Ideally take the media out of the 3+ and fit it into the first section of the new filter. You may need to remove some media to do this, but you could gradually change that back out once things are established.
 
Always worth keeping an eye out for new dead spots when you mess with the flow, particularly with 2 separate pumps as there can be strange currents at times.
 
Otherwise, watch for mini cycles. Small ammonia spikes aren't uncommon when you do things like this. It may be worth holding off feeding for a day or so before the change and a day or so after (much as you'd do if you went away) to try to minimise the change over ammonia levels.